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After World War II drew to a close in the mid-20th century, a new conflict began. Known as the Cold War, this battle pitted the world's two great powers-the democratic, capitalist United States and the communist Soviet Union-against each other. Beginning in the late 1950s, space became another dramatic arena for this competition, as each side sought to prove the superiority of its technology, its military firepower and-by extension-its political-economic system.

Causes of the Space Race

By the mid-1950s, the U.S.-Soviet Cold War had worked its way into the fabric of everyday life in both countries, fueled by the arms race and the growing threat of nuclear weapons, wide-ranging espionage and counter-espionage between the two countries, war in Korea and a clash of words and ideas carried out in the media. These tensions would continue throughout the space race, exacerbated by such events as the construction of the Berlin Wall in 1961, the Cuban missile crisis of 1962 and the outbreak of war in Southeast Asia.

Space exploration served as another dramatic arena for Cold War competition. On October 4, 1957, a Soviet R-7 intercontinental ballistic missile launched Sputnik (Russian for "traveler"), the world's first artificial satellite and the first man-made object to be placed into the Earth's orbit. Sputnik's launch came as a surprise, and not a pleasant one, to most Americans. In the United States, space was seen as the next frontier, a logical extension of the grand American tradition of exploration, and it was crucial not to lose too much ground to the Soviets. In addition, this demonstration of the overwhelming power of the R-7 missile-seemingly capable of delivering a nuclear warhead into U.S. air space-made gathering intelligence about Soviet military activities particularly urgent.

Did you know? After Apollo 11 landed on the moon's surface in July 1969, six more Apollo missions followed by the end of 1972. Arguably the most famous was Apollo 13, whose crew managed to survive an explosion of the oxygen tank in their spacecraft's service module on the way to the moon.

NASA Is Created

In 1958, the United States launched its own satellite, Explorer I, designed by the U.S. Army under the direction of rocket scientist Wernher von Braun. That same year, President Dwight D. Eisenhower signed a public order creating the National Aeronautics and Space Administration ( NASA), a federal agency dedicated to space exploration.

Eisenhower also created two national security-oriented space programs that would operate simultaneously with NASA's program. The first, spearheaded by the U.S. Air Force, dedicated itself to exploiting the military potential of space. The second, led by the Central Intelligence Agency ( CIA), the Air Force and a new organization called the National Reconnaissance Office (the existence of which was kept classified until the early 1990s) was code-named Corona; it would use orbiting satellites to gather intelligence on the Soviet Union and its allies.

Space Race Heats Up: Men (And Chimps) Orbit Earth

In 1959, the Soviet space program took another step forward with the launch of Luna 2, the first space probe to hit the moon. In April 1961, the Soviet cosmonaut Yuri Gagarin became the first person to orbit Earth, traveling in the capsule-like spacecraft Vostok 1. For the U.S. effort to send a man into space, dubbed Project Mercury, NASA engineers designed a smaller, cone-shaped capsule far lighter than Vostok; they tested the craft with chimpanzees and held a final test flight in March 1961 before the Soviets were able to pull ahead with Gagarin's launch. On May 5, astronaut Alan Shepard became the first American in space (though not in orbit).

Later that May, President John F. Kennedy made the bold, public claim that the U.S. would land a man on the moon before the end of the decade. In February 1962, John Glenn became the first American to orbit Earth, and by the end of that year, the foundations of NASA's lunar landing program-dubbed Project Apollo -were in place.

Achievements of Apollo

From 1961 to 1964, NASA's budget was increased almost 500 percent, and the lunar landing program eventually involved some 34,000 NASA employees and 375,000 employees of industrial and university contractors. Apollo suffered a setback in January 1967, when three astronauts were killed after their spacecraft caught fire during a launch simulation. Meanwhile, the Soviet Union's lunar landing program proceeded tentatively, partly due to internal debate over its necessity and to the untimely death (in January 1966) of Sergey Korolyov, chief engineer of the Soviet space program.

December 1968 saw the launch of Apollo 8, the first manned space mission to orbit the moon, from NASA's massive launch facility on Merritt Island, near Cape Canaveral, Florida. On July 16, 1969, U.S. astronauts Neil Armstrong, Edwin "Buzz" Aldrin and Michael Collins set off on the Apollo 11 space mission, the first lunar landing attempt. After landing successfully on July 20, Armstrong became the first man to walk on the moon's surface; he famously called the momen t "one small step for man, one giant leap for mankind."

Who Won the Space Race?

By landing on the moon, the United States effectively "won" the space race that had begun with Sputnik's launch in 1957. For their part, the Soviets made four failed attempts to launch a lunar landing craft between 1969 and 1972, including a spectacular launch-pad explosion in July 1969. From beginning to end, the American public's attention was captivated by the space race, and the various developments by the Soviet and U.S. space programs were heavily covered in the national media. This frenzy of interest was further encouraged by the new medium of television. Astronauts came to be seen as the ultimate American heroes, and earth-bound men and women seemed to enjoy living vicariously through them. Soviets, in turn, were pictured as the ultimate villains, with their massive, relentless efforts to surpass America and prove the power of the communist system.

With the conclusion of the space race, U.S. government interest in lunar missions waned after the early 1970s. In 1975, the joint Apollo-Soyuz mission sent three U.S. astronauts into space aboard an Apollo spacecraft that docked in orbit with a Soviet-made Soyuz vehicle. When the commanders of the two crafts officially greeted each other, their " handshake in space " served to symbolize the gradual improvement of U.S.-Soviet relations in the late Cold War era.

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The Space Race: Timeline, Cold War & Facts | HISTORY

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The Space Race refers to the period of competition over space exploration between the U.S. and the U.S.S.R. during the Cold War.

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A legacy of achievement stands out during National Women's History Month in March.

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Lovelace's Woman in Space Program was a short-lived, privately-funded project testing women pilots for astronaut fitness in the early 1960s. Although nothing concrete resulted, the women who participated have since been recognized as trailblazers, whose ambitions to fly the newest and the fastest craft led them to be among the first American women to gain access to sophisticated aerospace medical tests.

The Woman in Space Program began as an Air Force project that grew out of two researchers' interests in women's capabilities for spaceflight. Because, on the average, women are smaller and lighter than men are, scientists speculated that they might make good occupants for cramped space vehicles. In 1960, Dr. William Randolph "Randy" Lovelace II and Brig. General Donald Flickinger invited award-winning pilot Geraldyn "Jerrie" Cobb to undergo the physical testing regimen that Lovelace's Albuquerque, New Mexico Foundation had developed to help select NASA's first astronauts. Although the Lovelace Foundation for Medical Education and Research was a private organization, Dr. Lovelace also served as head of NASA's Special Committee on Bioastronautics. When Cobb became the first woman to pass those tests, Lovelace announced her success at a 1960 conference in Stockholm, Sweden. As Cobb coped with the ensuing publicity, Lovelace invited more women pilots to take the tests. Jacqueline Cochran, the famous pilot, businesswoman, and Lovelace's old friend, joined the project as an advisor and paid all of the women's testing expenses.

By the end of the summer of 1961, nineteen women pilots had taken astronaut fitness examinations at the Lovelace Clinic. Unlike NASA's male candidates, who competed in group, each woman came to Albuquerque either alone or in a pair for the week of tests. All of the women were skilled airplane pilots with commercial ratings. Most of them were recruited through the Ninety-Nines, a women pilot's organization. Others heard about the testing through friends or newspaper articles and volunteered. The oldest candidate, Jane Hart, was a forty-one year old mother of eight and the wife of a U.S. Senator (Philip Hart-D of Michigan). The youngest, Wally Funk, was a twenty-three year old flight instructor .

Since no human being had flown in space yet when the astronaut fitness tests were designed, the Lovelace doctors required very thorough examinations. These included numerous X-rays and a four-hour eye exam. A specially weighted stationary bicycle pushed the women to exhaustion while testing their respiration. The doctors had the women swallow a rubber tube so that they could test their stomach acids. A tilt table tested circulation. Using an electrical pulse, the physicians tested nerve reflexes in their arms. Ice water was shot into the women's ears to induce vertigo so that the doctors could time how quickly they recovered. They calculated the candidates' lean body mass using a nuclear counter in Los Alamos. By the end of the week, the women had no secrets from the Lovelace physicians.

In the end, thirteen women passed the same physical examinations that the Lovelace Foundation had developed for NASA's astronaut selection process. Those thirteen women were:
Jerrie Cobb
Wally Funk
Irene Leverton (now deceased)
Myrtle "K" Cagle
Jane B. Hart (now deceased)
Gene Nora Stumbough [Jessen]
Jerri Sloan [Truhill] (now deceased)
Rhea Hurrle [Woltman]
Sarah Gorelick [Ratley]
Bernice "B" Trimble Steadman (now deceased)
Jan Dietrich (now deceased)
Marion Dietrich (now deceased)
Jean Hixson (now deceased)

A few women took additional tests. Jerrie Cobb, Rhea Hurrle, and Wally Funk went to Oklahoma City for an isolation tank test and psychological evaluations. Because of other family and job commitments, not all of the women were asked to take these tests, however. Instead, the group prepared to gather in Pensacola, Florida at the Naval School of Aviation Medicine to undergo advanced aeromedical examinations using military equipment and jet aircraft. Two of the women quit their jobs in order to be able to attend. A few days before they were to report, however, the women received telegrams abruptly canceling the Pensacola testing. Without an official NASA request to run the tests, the Navy would not allow the use of their facilities for an unofficial project.

Jerrie Cobb immediately flew to Washington, D.C. to try to have the testing program resumed. She and Jane Hart wrote to President John Kennedy and visited Vice President Lyndon Johnson. Finally, on the 17th and 18th of July 1962, Representative Victor Anfuso (R) of New York convened public hearings before a special Subcommittee of the House Committee on Science and Astronautics. Significantly, the hearings investigated sex discrimination two full years before the 1964 Civil Rights Act made that illegal, making these hearings a marker of how ideas about women's rights permeated political discourse even before they were enshrined in law. Cobb and Hart testified about the benefits of Lovelace's private project. Jackie Cochran talked about her concerns that setting up a special program to train a woman astronaut could hurt the space program. NASA representatives George Low and Astronauts John Glenn and Scott Carpenter testified that the women could not qualify as astronaut candidates. NASA required all astronauts to be graduates of military jet test piloting programs and have engineering degrees. In 1962, no women could meet these requirements. Although the Subcommittee was sympathetic to the women's arguments, no action resulted.

Lovelace's privately-funded women's testing project received renewed media attention when Soviet cosmonaut Valentina Tereshkova became the first woman in space in 1963. In response, Clare Booth Luce published an article in Life magazine criticizing NASA and American decision makers. By including photographs of all thirteen Lovelace finalists, the names of all thirteen women became public for the first time. (Significant media coverage had already spotlighted some of the participants, however.)

Although both Cobb and Cochran made separate appeals for years afterward to restart a women's astronaut testing project, the U.S. civil space agency did not select any female astronaut candidates until the 1978 class of Space Shuttle astronauts. Astronaut Sally Ride became the first American woman in space in 1983 on STS-7, and Eileen Collins was the first woman to pilot the Space Shuttle during STS-63 in 1995. Collins also became the first woman to command a Space Shuttle mission during STS-93 in 1999. In 2005, she commanded NASA's return to flight mission, STS-114. At Collins' invitation, eight of the eleven surviving Lovelace finalists attended her first launch and she has flown mementos for almost all of them. The women of Lovelace's Woman in Space Program feel a special kinship with Collins, who in the 1990s finally fulfilled their thirty-year dream of seeing an American woman pilot astronaut.

Margaret A. Weitekamp, Author
Steve Garber, NASA History Web Curator
For further information email hq-histinfo@nasa.gov

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Todd Messer, Claire Rojstaczer, and Steve Garber

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Project Mercury - America's First Astronauts

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NASA.gov brings you the latest images, videos and news from America's space agency. Get the latest updates on NASA missions, watch NASA TV live, and learn about our quest to reveal the unknown and benefit all humankind.

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NASA.gov brings you the latest images, videos and news from America's space agency. Get the latest updates on NASA missions, watch NASA TV live, and learn about our quest to reveal the unknown and benefit all humankind.

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This is the mother of all hacks, the genius device that saved the Apollo XIII crew from dying in their emergency return to Earth, as photographed during that trip using one of their Hasselblad cameras. Here are the actual step-by-step instructions that helped turn this mission into NASA's most successful failure ever.

Why did they have to make this?

After Mission Control decided to cancel Apollo XIII's moon landing following an explosion of an oxygen tank in the Service Module, the astronauts moved to the Lunar Module in order to save power that was going to be needed later for re-entry.

The only problem with this plan was that the Lunar Module was designed for only two people for a 36-hour period, not three astronauts for 96 hours. They quickly discovered that carbon dioxide was building up fast, putting their lives in extreme danger. They had to change the circular CO2 scrubbers in the Lunar Module for clean ones, but they only had spare square CO2 scrubbers from the Command Module.

In record time, the Crew Systems Division put together an improvised adapter using all sort of weird and random parts, like a flight manual cover, suit parts, and socks. CAPCOM (Capsule Communicator) transmitted the instructions to the astronauts in order to assemble this "mailbox" rig-as they called it-working against the clock and trying to surive fight the effects of the poisonous gas which was quickly asphyxiating their brains.

INTRODUCTION

This procedure, which takes approximately one hour to complete, will allow the fitting of a square Odyssey Command Module (CM) scrubber filter through the Aquarius Lunar Module's (LM) round mounted filtration hole and will modify the Environmental Systems scrubber unit. The material is for astronauts to use when CO2 scrubbers fail in the CM, all CM filters are used or in other situations where additional scrubbing of CO2 is required. Crew Systems Division assembled and tested this information.

REQUIRED EQUIPMENT and MATERIALS

All required equipment is contained onboard within the Apollo 13 CM and LM.

Cover to the Apollo 13 flight plan (to cover and protect the hose entry)

2 lithium-hydroxide canisters

Roll of gray duct tape

2 LCG bags

2 hoses from the red suits

2 socks

1 bungee cord (to secure the modified filtration device to the wall of the LM)

PROCEEDURE - 19 steps

#1) Place the LCG bag over the top of the square lithium-hydroxide canister. The bag must be pulled down to just over the triangular ventilator slots on the side.

NOTE: Be careful not to rip the bag because there are only three bags onboard.

#2) Tear the duct tape down the middle lengthwise to double the linear length.

#3) Seal the bag to the square canister by wrapping the duct tape around the canister where the bag opening is.

NOTE: The tape must seal the opening to prevent leakage of air flow.

#4) Poke or cut a hole in the middle of the top of the covering bag approximately the diameter of the hose from the red suit.

#5) Insert the hose into the hole. Secure the hose connection into the LCG bag with duct tape.

NOTE: The tape must seal the opening to prevent leakage of air flow.

#6) Cover the top of the LCG bag and hose attachment with the flight plan cover in an arch. The hose will stick out of one side of the arch.

#7) Attach the two sides of the cardboard flight plan cover that make contact with the square filter using a six inch long piece of duct tape over the top. This will prevent crushing the hose and air entry on the final mounting in step #19.

#8) Wrap the entire top sides of the filter cube with a three foot (about an arms length) piece of duct tape. Repeat wrapping on the bottom of the sides of the cube.

NOTE: The tape must seal the opening to prevent leakage of air flow.

#9) Secure the bag with strips of duct tape two per side running from one side, under the bottom and back up the other side. Repeat on the other side. The bottom of the cube will resemble a tic tac toe board when this step is completed.

#10) Stuff the sock into the ventration hole in the center of the square scrubber. This will prevent the air from bypassing the filter. Cover the hole with a couple of pieces of tape to keep it from falling out.

#11) Repeat steps #3 through #10 for the second canister. This will be the replacement when the first filter becomes saturated.

#12) Open the sensor relief valve. This will normalize the pressure and allow you to attach the hose to the intake valve.

#13) Attach the free end of the hose to the scrubber intake.

#14) Attach the end of the bungee cord to the hook above the lithium canister mounting location on the bulkhead.

#15) Secure the canister to the bulkhead by hooking the other end of the bungee cord below the mounting location.

#16) Attach the crossover hose to the secondary air cleaner.

#17) Close the sensor relief valve opened in step 12.

#18) Set the CO2 select to secondary using the LM air cleaner selection switch on panel eleven.

#19) Engage the air cleaning scrubber fan by flipping the ACSF switch located on panel eleven.

VERIFICATION

Check the CO2 levels on the partial pressure (marked PART PRES C02) meter on panel eleven. The level should begin to fall (safe level of partial pressure is below eight (8)). Further verification will be indicated through the amber CO2 warning light set to illuminate if the level is above ten (10).

Reminder: CO2 levels above 15 can be fatal and will cause brain asphyxia, impaired judgment and blackouts

TROUBLESHOOTING

If the canister seals are not correct in steps #3, #5 and #8, CO2 cleaning may not be adequate. You will recognize this if you hear a whooshing sound when the system starts. Re-tape the seal that is leaking.

If the LCG bags get ripped air flow may leak out and fail to clean the CO2. Use the spare bag if this happens.

That's John L. Swigert working on the "mailbox" rig with Jim Lovell. It seems amazing to me that he looks so calm and cool when they were actually being poisoned by their own CO2 and without knowing if they were going to make it alive to Earth. The actual scrubber in the upper hatch tunnel as shot from the Lunar Module.
The Apollo XIII movie did a great job at replicating all this:
Above: View of the service module after the separation of the command module. The destruction on the side of the module is obvious. It was a miracle that these guys survived the first explosion. After that, it was an outstanding combination of ingenuity, training, courage, and sheer luck that saved their lives on their trip back home. Safe back on Earth: Fred W. Haise, James A. Lovell, and John L. "Jack" Swigert.
SPLOID is a new blog about awesome stuff.

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This is the actual hack that saved the astronauts of the Apollo XIII

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This is the mother of all hacks, the genius device that saved the Apollo XIII crew from dying in their emergency return to Earth, as photographed during that trip using one of their Hasselblad cameras. Here are the actual step-by-step instructions that helped turn this mission into NASA's most successful failure ever.

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NASA.gov brings you the latest images, videos and news from America's space agency. Get the latest updates on NASA missions, watch NASA TV live, and learn about our quest to reveal the unknown and benefit all humankind.

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Toggle the table of contents

From Wikipedia, the free encyclopedia

A replica of Luna 9, the first spacecraft to land on the Moon

The first image taken of the far side of the Moon, returned by Luna 3

As part of human exploration of the Moon, numerous space missions have been undertaken to study Earth's natural satellite. Of the Moon landings, Luna 2 of the Soviet Union was the first spacecraft to reach its surface successfully,[1] intentionally impacting the Moon on 13 September 1959. In 1966, Luna 9 became the first spacecraft to achieve a controlled soft landing,[2] while Luna 10 became the first mission to enter orbit.

Between 1968 and 1972, crewed missions to the Moon were conducted by the United States as part of the Apollo program. Apollo 8 was the first crewed mission to enter orbit in December 1968, and it was followed by Apollo 10 in May 1969. Six missions landed humans on the Moon, beginning with Apollo 11 in July 1969, during which Neil Armstrong became the first person to walk on the Moon. Apollo 13 was intended to land; however, it was restricted to a flyby due to a malfunction aboard the spacecraft. All nine crewed missions returned safely to the Earth.

While the United States focused on the crewed Apollo program, the Soviet Union conducted uncrewed missions that deployed rovers and returned samples to the Earth. Three rover missions were launched, of which two were successful, and eleven sample return flights were attempted with three successes.

Missions to the Moon have been conducted by the following nations and organisations (in chronological order): the Soviet Union, the United States, Japan, the European Space Agency, China, India, Luxembourg, Israel, Italy, South Korea, and the United Arab Emirates. The Moon has also been visited by five spacecraft not dedicated to studying it; four spacecraft have flown past it to gain gravity assistance, and a radio telescope, Explorer 49, was placed into selenocentric orbit in order to use the Moon to block interference from terrestrial radio sources.

Country

Flyby

Orbit

Impact

Lander

Rover

Return

Crewed landing

Map of all soft landings

Mission

Spacecraft

Launch date

Carrier rocket

Operator

Mission type

Outcome

Pioneer 0

(Able I)[3]

Pioneer 0

17 August 1958

Orbiter

Launch failure

Pioneer 1

(Able II)[3]

Pioneer 1

11 October 1958

Orbiter

Launch failure

Pioneer 2

(Able III)

Pioneer 2

8 November 1958

Thor DM-18 Able I

Orbiter

Launch failure

Pioneer 3

Pioneer 3

6 December 1958

Juno II

Flyby

Launch failure

Luna 1

2 January 1959

Luna

Impactor

Partial failure

Carrier rocket guidance problem resulted in failure to impact Moon, flew past in a heliocentric orbit.[9] Closest approach 5,995 kilometres (3,725 mi) on 4 January.[10] First spacecraft to fly by the Moon.

Pioneer 4

Pioneer 4

3 March 1959

Juno II

Flyby

Partial failure

Successful impact at 21:02 on 14 September 1959. First spacecraft to reach lunar surface.[12] The impact made the Soviet Union the 1st country to reach the surface of the Moon.

Returned first images of the far side of the Moon.[13]

Failed to deploy solar panels, ran out of power ten hours after launch; incidental impact on the far side of the Moon on 26 April. First spacecraft to impact the far side of the Moon.[18][20] The impact made the United States the 2nd country to reach the surface of the Moon.

Solar panels erroneously disengaged from power system, failed 8+ 3⁄4 hours after launch when batteries were depleted.[18] Missed the Moon as course correction was not completed.[21]

Failed to perform mid-course correction,[23] remained in high Earth orbit until given escape velocity by orbital perturbation.[24]

Engine failed to shut down after performing mid-course correction manoeuvre,[28] flew past the Moon in a heliocentric orbit.[33]

First spacecraft to land successfully on the Moon. Touchdown on 3 February 1966 at 18:45:30 UTC.[37] Returned data until 6 February at 22:55 UTC.[38]

Entered orbit at 18:44 UTC on 3 April 1966, becoming the first spacecraft to orbit the Moon.[40] Continued to return data until 30 May.[38]

Landed in Oceanus Procellarum on 2 June 1966 at 06:17:36 UTC.[38] Returned data until loss of power on 13 July.[41]

Entered orbit on 28 August 1966. Failed to return images; other instruments operated correctly.[38] Conducted gamma ray and X-ray observations to study the composition of the Moon, investigated the lunar gravitational field, the presence of meteorites in the lunar environment and the radiation environment at the Moon. Ceased operations on 1 October 1966 after power was depleted.[44]

Successfully landed in Oceanus Procellarum at 18:01 UTC on 24 December 1966.[38] Returned images from the surface and studied the lunar soil.[48] Operated until depletion of power at 06:31 UTC on 28 December.[38]

Landed at 00:04 UTC on 20 April 1967 and operated until 3 May.[50][51] Visited by Apollo 12 astronauts in 1969, with some parts removed for return to Earth.[52]

19 July 1967

Delta E1

Orbiter

Successful

Final mission in the Lunar Orbiter series, entered selenocentric orbit on 5 August at 16:48 UTC and conducted a photographic survey until 18 August. Deorbited and impacted the Moon on 31 January 1968.[57]

Landed in Mare Tranquillitatis at 00:46:44 UTC on 11 September. Last signals received at 04:30 UTC on 17 December 1967.[58]

Landed in Sinus Medii at 01:01:04 UTC on 10 November.[50] Made brief flight from lunar surface at 10:32 UTC on 17 November, followed by second landing after travelling 2.4 metres (7 ft 10 in). Last contact at 19:14 UTC on 14 December.[59]

Surveyor 7

Surveyor 7

7 January 1968

Atlas SLV-3C Centaur-D

Lander

Successful

Final Surveyor mission.[60] Landed 29 kilometres (18 mi) from Tycho crater at 01:05:36 UTC on 10 January. Operated until 21 February 1968.[61]

Tested communications for proposed crewed missions and studied the mass concentration of the Moon. Entered orbit on 10 April at 19:25 UTC.[62]

Two tortoises and other life forms on board a technology demonstration for planned crewed missions. Made a closest approach of 1,950 kilometres (1,210 mi) on 18 September, and circled the Moon before returning to Earth. Landed in the Indian Ocean on 21 September at 16:08 UTC, becoming the first Lunar spacecraft to be recovered successfully and carried the first Earth life to travel to and around the Moon.[63]

First crewed mission to the Moon; entered orbit around the Moon with four-minute burn beginning at 09:59:52 UTC on 24 December. Completed ten orbits of the Moon before returning to Earth with an engine burn at 06:10:16 UTC on 25 December. Landed in the Pacific Ocean at 15:51 UTC on 27 December.[65]

First crewed landing on the Moon. The Lunar Module Eagle landed at 20:17 UTC on 20 July 1969.

Third attempt at lunar sample return. After reaching low Earth orbit, the fourth-stage engine failed to fire for trans-lunar injection due to oxidiser leak. Spacecraft re-entered Earth's atmosphere about 4 days after launch.[67]

Second crewed lunar landing.

Failed to orbit

Lunar landing aborted following Service Module oxygen tank explosion en route to the Moon; flew past the Moon (free-return trajectory) and returned the crew safely to Earth.

First robotic sampling mission.

Technology demonstration for planned crewed missions; returned to Earth successfully.

Luna 17 deployed Lunokhod 1.

Third crewed lunar landing.

Fourth crewed lunar landing, and first to use the Lunar Roving Vehicle.

PFS-1 was deployed from Apollo 15.

Failed during descent to lunar surface.

Luna 19

28 September 1971

Proton-K/ D

Orbiter

Successful

Entered an orbit around the Moon on 2 October 1971 after two midcourse corrections on 29 September and 1 October.

Luna 20 soft landed on the Moon in a mountainous area known as the Terra Apollonius (or Apollonius highlands) near Mare Fecunditatis (Sea of Fertility), 120 km from where Luna 16 had landed.

5th crewed lunar landing.

PFS-2 deployed from Apollo 16.

Failed to orbit; intended to orbit the Moon and return to Earth.

Deployed Lunokhod 2.

Radio astronomy spacecraft, operated in selenocentric orbit to avoid interference from terrestrial radio sources.

Interplanetary spacecraft, mapped lunar north pole to test cameras.

Inserted into a circular lunar orbit on 2 June 1974

Tipped over upon landing, precluding any sample return attempt. Functioned for three days on surface.

Luna E-8-5M No.412

Luna E-8-5M No.412

16 October 1975

Proton-K/ D

Lander

Launch failure

Failed to orbit.

Final mission of the Luna programme. Entered orbit on 11 August 1976 and landed in Mare Crisium at 16:36 UTC on 18 August. Sample capsule launched at 05:25 UTC on 19 August and recovered 96+ 1⁄2 hours later.[69] Returned 170.1 grams (6.00 oz) of lunar regolith.[70] Final mission to the Moon from the Soviet Union.

Five flybys in 1982 and 1983 en route to comet 21P/Giacobini-Zinner.

Hagoromo

24 January 1990

Mu-3S-II

Orbiter

Spacecraft failure

Designed for flyby, placed into selenocentric orbit during extended mission after failure of Hagoromo. Deorbited and impacted in USGS quadrangle LQ27 on 10 April 1993.[71] Hagoromo was deployed from Hiten. The impact made Japan the 3rd country to reach the surface of the Moon.

Geotail

Geotail

24 July 1992

Delta II 6925

ISAS/ NASA

Flyby

Successful

Series of flybys to regulate high Earth orbit.

Made two flybys on 1 December 1994 and 27 December 1994 to reach the Earth-Sun L1 Lagrangian point.

Clementine

(DSPSE)

Clementine

25 January 1994

Titan II (23)G Star-37FM

USAF/ NASA

Orbiter

Successful

Completed Lunar objectives successfully; failed following departure from selenocentric orbit.

Communications satellite; made two flybys in May and June 1998 en route to geosynchronous orbit after delivery into wrong orbit.

The mission ended on July 31, 1999

Two flybys en route to Mars.

Flyby on 30 July 2001 to reach the Earth-Sun L2 Lagrangian point.

Impacted Moon in USGS quadrangle LQ26 at end of mission on 3 September 2006. The impact made ESA member states the 4th to reach the surface of the Moon.

STEREO B

Successful

Both component spacecraft entered heliocentric orbit on 15 December 2006.

Two THEMIS spacecraft moved to selenocentric orbit for extended mission; entered orbit July 2011.

Deployed Okina and Ouna satellites. Kaguya and Okina impacted the Moon at end of mission.[72] Ouna completed operations on 29 June 2009[73] but remains in selenocentric orbit.

Succeeded through mission. Orbit lasted 312 days, short of intended 2 years; However mission achieved most of its intended objectives. Terminated in 2009, remains in selenocentric orbit; discovered water ice on the Moon.[74] Moon Impact Probe was deployed from the orbiter. It successfully impacted Moon's Shackleton Crater in the USGS quadrangle LQ30 at 20:31 on 14 November 2008 releasing underground debris that could be analysed by the orbiter for presence of water/ice. With this mission, India became the first to hard land or impact on Lunar south pole and the fifth nation to reach the lunar surface.

Entered orbit on June 23, 2009

Observed impact of Centaur upper stage that launched it and LRO, then impacted itself. Impacts in USGS quadrangle LQ30.

Following completion of six month Lunar mission, departed selenocentric orbit for Earth-Sun L2 Lagrangian point;[75] subsequently flew by asteroid 4179 Toutatis.[76]

GRAIL

10 September 2011 [77][78]

Delta II 7920H

Orbiter

Successful

Orbiter

Successful

Mission ended on 18 April 2014, when the spacecraft's controllers intentionally crashed LADEE into the far side of the Moon.

Yutu

Rover

Successful

Entered orbit on 6 December 2013 with landing at 13:12 UTC on 14 December. Yutu rover was deployed from Chang'e 3.

Demonstration of re-entry capsule for Chang'e 5 sample-return mission at lunar return velocity.

Attached to third stage of CZ-3C used to launch Chang'e 5-T1. Impacted the Moon on 4 March 2022. The impact made Luxembourg the 8th country to reach the surface of the Moon.

Entered designated Earth-Moon L₂ orbit on 14 June in preparation of Chang'e 4 far-side lunar lander in December 2018.

Launched on the same rocket as Queqiao. Longjiang-1 never entered Moon orbit,[81] while Longjiang-2 operated in lunar orbit until 31 July 2019, when it impacted the lunar surface.[82]

First spacecraft to soft land on the far side of the Moon ( South Pole-Aitken basin). Landed 3 January 2019 and deployed the Yutu-2 rover.[83][84]

First Israeli and first privately funded lunar lander mission. Technology demonstration. Instrumentation included a magnetometer and laser retroreflector.[85][86] Spacecraft crashed into the lunar surface after main engine failure during descent from lunar orbit phase.[87] The impact made Israel the 7th country to reach the surface of the Moon.

Chandrayaan-2

Chandrayaan-2 Orbiter

22 July 2019

LVM3 M1

Orbiter

Operational

Vikram

Lander

Spacecraft Failure

CAPSTONE

CAPSTONE

28 June 2022[90]

Electron

Orbiter

Operational

Danuri

( Korea Pathfinder Lunar Orbiter)

Danuri

4 August 2022[90]

Falcon 9

Operational

Lunar Orbiter by the Korea Aerospace Research Institute (KARI) of South Korea. The orbiter, its science payload and ground control infrastructure are technology demonstrators. The orbiter will also be tasked with surveying lunar resources such as water ice, uranium, helium-3, silicon, and aluminium, and produce a topographic map to help select future lunar landing sites.

Artemis 1

Artemis 1 Orion MPCV CM-002

16 November 2022[93]

SLS Block 1

Orbiter

Successful

LunaH-Map and Lunar IceCube

LunaH-Map

16 November 2022

SLS Block 1

Orbiter

En route

H-Map will search for evidence of lunar water ice inside permanently shadowed craters using its neutron detector while, IceCube will uses its infrared spectrometer to detect water and organic compounds in the lunar surface and exosphere.

It is to flyby the Moon and collect its surface thermography.

Near-Earth Asteroid Scout

Near-Earth Asteroid Scout

16 November 2022

SLS Block 1

Flyby

Spacecraft failure

EQUULEUS

EQUULEUS

16 November 2022

SLS Block 1

Flybys

Operational

OMOTENASHI

OMOTENASHI

16 November 2022

SLS Block 1

Impactor

Spacecraft failure

It was a lunar surface probe attempting to semi-hard land using solid rocket motors. Carrier and solid motor was to impact. Communication failure occurred and the probe missed and flew by the Moon.

CubeSat spacecraft on an astrobiology mission that will use budding yeast to detect, measure, and compare the impact of deep space radiation on DNA repair over long time beyond low Earth orbit.

CubeSat to orbit the Sun to study the dynamic particles and magnetic fields.

Team Miles

Team Miles

16 November 2022

SLS Block 1

Fluid & Reason

Flyby

Successful

CubeSat that will demonstrate navigation in deep space using innovative plasma thrusters.

SORA-Q

11 December 2022

Falcon 9 Block 5

Tomy/ JAXA/ Dodai

Rover

Spacecraft failure

Emirates Lunar Mission

Rashid

11 December 2022

Falcon 9 Block 5

UAESA/ MBRSC

Rover

Spacecraft failure

Lunar rover demonstration. Launched aboard ispace's Hakuto-R lander.[96] Lost with Hakuto-R. The impact made the United Arab Emirates the 9th country to reach the surface of the Moon.

Initially scheduled to be launched on the Artemis 1 mission, moved to a Falcon 9 Block 5 after not making it for the payload integration deadline. NASA announced later that it would not make its planned orbit or monthly flybys due to thruster issues.[97][2]

Will fly by the Moon in August 2024 en route to Ganymede.

Launched 14 July 2023, scheduled to land 23 August 2023.

There are several future lunar missions planned or proposed by various nations and organisations.

Funded and are under development

Robotic

Agency or company

Mission

Name of spacecraft

Launch date

Launch vehicle

Notes

Luna 25

10 August 2023 23:10 (UTC)[98]

Soyuz-2.1b / Fregat

Lander will explore natural resources on Moon, part of Luna-Glob programme.

SLIM lander

26 August 2023 00:34 (UTC)

H-IIA 202

Pinpoint landing and roving.[100][101][102]

LEV-1

Hopper, carries multiple instruments

Tomy, JAXA, Doshisha University

LEV-2

Small commercial lunar orbiter

Colmena

5 Microrovers

Iris

CubeRover, technology demonstration

Khon1

Communication Satellite

Micro-nova

Hopper

Lunar Outpost

MAPP

Rover, communication technology demonstration

AstroAnt[109]

Micro rover, will travel on MAPP rover

Dymon

Small rover, mapping

SHEPRA-ES mission[111]

SHEPRA-ES

Lunar Flyby towards Geostationary orbit, payload delivery.

Lunar Trailblazer

Orbiter, lunar ice scouting.

Queqiao 2

Queqiao relay satellite 2

early 2024[112]

Long March 8

Tiandu-1[114]

2 orbiters, technology demonstration of lunar constellation.

Chang'e 6

Lander

May 2024[115]

Long March 5

Sample-return from the south pole Aitken basin on the far side of the Moon[116]

Orbiter

Ascent Vehicle

IM-3
Nova-C

Falcon 9

Third Nova-C. Lunar Vertex mission

Khon2

Communication Satellite

CADRE

4 small rovers, mapping

Lunar vertex

NASA organised rover

Blue Ghost M1

Blue Ghost

Mid 2024 [3]

Falcon 9

Lunar lander, carrying NASA-sponsored experiments and commercial payloads to Mare Crisium.[119][120]

Griffin Mission 1[121]

November 2024

Falcon Heavy

Will host the VIPER Rover

Will prospect for lunar resources in the south pole region, especially for water ice.

PPE and HALO[123]

November 2024

Falcon Heavy

Key elements of Lunar Gateway.

Demo mission

Q4 2024

Starship

Uncrewed demo mission of Starship HLS

DESTINY+

2024[125]

Epsilon S

Lunar flyby toward asteroid 3200 Phaethon

Ispace rover

SERIES 2

2025[127]

TBD

Lunar lander part of CLPS program

Orbiter

2025

TBD

One orbiter, Two landers.

Lander 1

Lander 2

Blue Ghost M2[129]

Blue Ghost lander

2026

TBD

Second mission of Firefly Aerospace, part of CLPS, includes 2 stage variant of blue ghost.

transfer vehicle/relay satellite

Lunar Pathfinder

Lunar communications satellite to support future lunar missions.

Chang'e 7
Orbiter

2026[130]

Long March 5

Payloads include an orbiter, south pole lander, rover, and a mini flying probe to look for the presence of water-ice.[130]

Lander

Rover

Hopper

Starship cargo mission

2026

SpaceX Starship

First SpaceX lunar cargo mission, yet to be announced by SpaceX itself.

Large Lunar rover, can accommodate cargo and 2 astronauts.

2026

Falcon Heavy

Third lunar mission by Astrobotic, will land at south pole, Lander will be most likely Griffin judging by the launch vehicle.

Luna 26

2027[133]

Soyuz-2.1b / Fregat

Luna 27

2028[133]

Angara A5 / Fregat

Lander, part of Luna-Glob programme.

Chang'e 8

Orbiter

2028[135]

Long March 5

Lander

Rover

Hopper

SpaceX GLS-1[138]

2028

Falcon Heavy

First resupply mission to Lunar Gateway.

Uncrewed Demo mission [4]

Blue Moon

2028

New Glenn

Demo mission of Blue Moon lander system in preparation for crewed landing in 2029.

ESA

Argonaut Lander

TBD

Ariane 64

Robotic Lander system with rover, Robotic Sample Return.

Crewed

Proposed but full funding still unclear

Robotic

The following robotic space probe missions have been proposed but their full funding is unclear or not yet been requested:

Agency or company

Mission

Name of spacecraft

Proposed launch

Notes

Lunar Meteoroid Impact Observer

2026

Proposed CubeSat to observe asteroid impacts on Far side of Moon.

Lunar Polar Exploration Mission

LUPEX lander

2026-28 [146]

LUPEX rover

Garatéa-L

2025[148]

Proposed lunar CubeSat, Partnership between UKSA and ESA.

LSAS lander

2025

proposed commercial lander, will rideshare with a Geostationary satellite.

Chandrayaan-5
2025-30

On site sampling of lunar soil. Purposed within the time frame of 2025-30.[149]

Parsec lunar satellites

2025

Parsec lunar communication constellation.[150]

Lunar Trailblazer

2026

Under study for possible rover mission

Lunar zebro

2026

Small swarming rover, radiation measurements

ILRS 1-5

2026 - 2035

5 crucial missions planned for comprehensive establishment of ILRS to complete the in-orbit and surface facilities

Luna 28

2029[133]

Proposed Sample-return mission, part of Luna-Glob program, may include small rover.

Luna 29

Luna 29 Lander

2030s[133]

Proposed Sample-return mission, part of Luna-Glob program, Will include Luna-Grunt rover.

Luna-Grunt rover

Phase 2 of the Korean lunar exploration program

2030 [151]

Lander and rover

Zeus

2030

Nuclear Propelled Space Tug, might deliver payloads to the moon

Chandrayaan-6
2030-35

Sample return mission, to be launched within the time frame of 2030-35.[149]

BOLAS

TBD

Autonomous Impactor for Lunar Exploration

TBD

Impactor for LEAP

Lunar Crater Radio Telescope

TBD

Radio telescope made by 4 rovers

Lunar space elevator

TBD

Creating a reusable, replaceable and expandable Lunar elevator to open up the resources present on the Moon

LVICE²

TBD

Measuring the concentration of micrometeorites[153]

Lunar missions by organization/company

Country

Agency
or company

Successful

Partial Failure

Failure

Operational

Total

Total
(for country)

2010s

Resource Prospector - concept by NASA of a rover that would have performed a survey expedition on a polar region of the Moon. It was canceled in April 2018.[154]

1. ^

2. ^ "Zond 5". NASA Space Science and Data Coordinated Archive.

3. Siddiqi, Asif A. (2002). "1969" (PDF). Deep Space Chronicle: A Chronology of Deep Space and Planetary Probes 1958-2000. Monographs in Aerospace History, No. 24. NASA History Office. pp. 73-80.

4. ^

5. ^ "月周回衛星「かぐや（SELENE）」 - SELENE通信 - お知らせ" (in Japanese). JAXA. 30 June 2009. Archived from the original on 3 October 2011.

6. ^ Varanasi, P.; Tompkins, S.; Taylor, L. A.; Sunshine, J.; Staid, M.; Runyon, C.; Petro, N.; Nettles, J.; Mustard, J. (23 October 2009). "Character and Spatial Distribution of OH/H2O on the Surface of the Moon Seen by M3 on Chandrayaan-1". Science. 326 (5952): 568-572. Bibcode:2009Sci...326..568P. doi:10.1126/science.1178658. ISSN 0036-8075. PMID 19779151. S2CID 447133.

7. ^

8. ^ How China's lunar relay satellite arrived in its final orbit Archived 17 October 2018 at the Wayback Machine. Luyuan Xu, The Planetary Society. 15 June 2018.

9. ^ @planet4589 (31 July 2019). "The Chinese Longjiang-2 (DSLWP-B) lunar orbiting spacecraft completed its mission on Jul 31 at about 1420 UTC, in a planned impact on the lunar surface" (Tweet) - via Twitter.

10. ^ "小型探査機による高精度月面着陸の技術実証（SLIM）について" (PDF) (in Japanese). 3 June 2015. Archived (PDF) from the original on 22 June 2015.

11. ^ "Small lunar-lander "SLIM" for the pinpoint landing technology demonstration" (PDF). 2015. Archived (PDF) from the original on 28 March 2017.

12. ^ "The tiny rover payload in SLIM mission" (PDF). 2015. Archived (PDF) from the original on 22 June 2015.

13. ^ China N' Asia Spaceflight [@CNSpaceflight] (24 November 2022). "Update:
2024 Queqiao-2 data relay
2025 Chang'e-6 lunar sample return from far side
2026 Chang'e-7 lunar landing in south pole
2028 Chang'e-8 basic model of lunar research station" (Tweet) - via Twitter.

14. "China advances lunar exploration programdate=April 25, 2023".

15. ^ Andrew Jones [@AJ_FI] (25 April 2023). "China's Chang'e-6 sample return mission (a first ever lunar far side sample-return) is scheduled to launch in May 2024, and expected to take 53 days from launch to return module touchdown. Targeting southern area of Apollo basin (~43º S, 154º W)" (Tweet) - via Twitter.

16. ^ Crain, Timothy (18-20 July 2022). Commercial Capabilities to Support Lunar Exploration - Intuitive Machines (PDF). John Glenn Memorial Symposium. Case Western Reserve University: American Astronautical Society. Archived (PDF) from the original on 12 November 2022.

17. ^ "A Big Rover Aims to Be Like 'UPS for the Moon'". Yahoo News.

18. ^ Russian Moon exploration program Archived 15 September 2018 at the Wayback Machine. Russian Research Institute (IKI). 2017.

19. ^ China's Deep Space Exploration Roadmap Archived 14 February 2019 at the Wayback Machine. 2018.

20. ^ [1]

21. ^ "ISRO to handhold private sector to create innovative space ecosystem in the country: S. Somanath, Chairman". Geospatial World. 11 April 2022. We are working with JAXA on developing a payload, as well as a mission to go to moon. This will be launched using Japan's launch vehicle, but the spacecraft will be jointly developed by ISRO and Japan. A lander which will land on the moon. This will be after Chandrayaan 3 It will take three, four, five years to develop.

22. ^ ISRO planning 7 interplanetary missions, Venus on the to-do list Archived 7 November 2020 at the Wayback Machine. Sidharth MP, DNA India. 18 May 2019.

23. Neeraj Srivastava; S. Vijayan; Amit Basu Sarbadhikari (27 September 2022), "Future Exploration of the Inner Solar Syetem: Scope and the Focus Areas", Planetary Sciences Division (PSDN), Physical Research Laboratory - via ISRO Facebook Panel Discussion, Mars Orbiter Mission National Meet

24. ^ https://www.korea.kr/news/policyNewsView.do?newsId=148885478 . Blue House, 문 대통령 "내년 달 궤도선·2030년 달 착륙...7대 우주강국 도약". 18 May 2021.

25. ^ Bi-Sat Observations of the Lunar Atmosphere Above Swirls (BOLAS): Tethered SmallSat Investigation of Hydration and Space Weathering Processes at the Moon. (PDF) Stubbs, T. J.; Malphrus, B. K.; Hoyt, R., etal. 49th Lunar and Planetary Science Conference; 19-23 March 2018 at The Woodlands, Texas, USA.

26. ^ "About the mission". esc Aerospace. 2023.

27. ^ NASA scraps a lunar surface mission - just as it's supposed to focus on a Moon return Archived 3 November 2018 at the Wayback Machine Loren Grush, The Verge April 27, 2018

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List of missions to the Moon - Wikipedia

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Toggle the table of contents From Wikipedia, the free encyclopedia As part of human exploration of the Moon, numerous space missions have been undertaken to study Earth's natural satellite. Of the Moon landings, Luna 2 of the Soviet Union was the first spacecraft to reach its surface successfully,[1] intentionally impacting the Moon on 13 September 1959.

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It was the 1960s, and the space race was on. In 1957, the Soviet Union built and launched Sputnik, the first man-made satellite. The citizens of the United States were shocked -- the idea that another country would beat the U.S. into space was unthinkable. Moreover, if the Soviet Union could launch a satellite into orbit, could it also fire a missile across the world?

The United States government acted quickly to reclaim its reputation as the most scientifically advanced country in the world. To that end, in 1961, President John F. Kennedy addressed Congress about the importance of the United States' role in space. In his speech, Kennedy proposed an ambitious goal: landing a man on the moon before the end of the decade [source: Home of Heroes].

The National Aeronautics and Space Administration ( NASA), which was formed in 1958, initiated the Apollo program with the intention of landing a man on the moon. From 1961 to 1972, the Apollo Program's mission was to transport astronauts safely to the moon and then return them to Earth. Remarkably, six of the Apollo missions achieved this goal.

NASA developed the Apollo spacecraft with the help of companies like Boeing, North American Rockwell, McDonnell Douglas, IBM and Grumman. Together, they constructed the complex machinery that could transport a small crew to the moon and back again. What was their creation like, and how did it help NASA fulfill Kennedy's promise?

Before we jump into the mechanics of the spacecraft, let's take a look at the history of the program.

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The Apollo program was initiated with the goal of landing a man on the moon. What was the spacecraft that helped make this giant leap for mankind?

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Adam Ruins Everything - Why the Moon Landing Couldn't Have Been Faked | truTV

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Mission Timeline

1961
Mercury Redstone 3 - 5 May 1961 - Earth Suborbital (Shepard)(Grissom)(Glenn)(Carpenter)(Schirra)(Cooper)
1964
1965
Gemini 3 - 23 March 1965 - Earth Orbiter(Grissom, Young)(McDivitt, White)(Cooper, Conrad)(Borman, Lovell)(Schirra, Stafford)(Armstrong, Scott)(Stafford, Cernan)(Young, Collins)(Conrad, Gordon)(Lovell, Aldrin)
1967
1968
Apollo 7 - 11 October 1968 - Earth Orbiter(Schirra, Eisele, Cunningham)(Borman, Lovell, Anders)(McDivitt, Scott, Schweikart)(Stafford, Young, Cernan)(Armstrong, Aldrin, Collins)(Conrad, Bean, Gordon)(Lovell, Haise, Swigert)(Shepard, Mitchell, Roosa)(Scott, Irwin, Worden)(Young, Duke, Mattingly)(Cernan, Schmitt, Evans)

Other Missions

Search for Mission Information

To search for information on any mission, enter the spacecraft name in the box below.

Author/Curator:
Dr. David R. Williams,dave.williams@nasa.gov
NSSDCA, Mail Code 690.1
NASA Goddard Space Flight Center
Greenbelt, MD 20771
+1-301-286-1258

NASA Official: Dave Williams, david.r.williams@nasa.gov
Last Updated: 12 April 2016, DRW

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1961 Mercury Redstone 3 - 5 May 1961 - Earth Suborbital (Shepard)(Grissom)(Glenn)(Carpenter)(Schirra)(Cooper) 1964 1965 Gemini 3 - 23 March 1965 - Earth Orbiter(Grissom, Young)(McDivitt, White)(Cooper, Conrad)(Borman, Lovell)(Schirra, Stafford)(Armstrong, Scott)(Stafford, Cernan)(Young, Collins)(Conrad, Gordon)(Lovell, Aldrin) 1967 1968 Apollo 7 - 11 October 1968 - Earth Orbiter(Schirra, Eisele, Cunningham)(Borman, Lovell, Anders)(McDivitt, Scott, Schweikart)(Stafford, Young, Cernan)(Armstrong, Aldrin, Collins)(Conrad, Bean, Gordon)(Lovell, Haise, Swigert)(Shepard, Mitchell, Roosa)(Scott, Irwin, Worden)(Young, Duke, Mattingly)(Cernan, Schmitt, Evans) To search for information on any mission, enter the spacecraft name in the box below.

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The Sun and Planets to Scale

&nbsp

1 pixel = 1000 kilometers

The apparent brightnesses of the planets cover too wide a range to depict accurately. This picture gives an idea of their relative brightnesses due to differences in size, color, and reflectivity, but not due to distance from the Earth or Sun. Only the largest moons and asteroids are shown.

&nbsp Equatorial &nbsp &nbsp Mean &nbsp &nbsp Escape &nbsp Rotation &nbsp Incl. &nbsp Visual

Diam. (km) Oblateness Mass Density Gravity (km/s) Period (days) (deg.) Albedo

Earth 12,756 1/298 1 5.52 1 11 .2 0 .9973 23 .4 0.37

Moons &nbsp Mass relative to Earth's mass, which is 5.974 x 10²⁴ kg.

Asteroids &nbsp Gravity and escape speed at the pole, at the visible surface.

Kuiper Belt Objects &nbsp Inclination of the equator relative to the plane of the orbit.

Comets * &nbsp The Sun's surface rotates faster at the equator than at the poles.

** &nbsp At the equator, where Jupiter's atmosphere rotates fastest.

The above table in plain text

&nbsp To my Space and Science home page&nbsp for more about the Solar System

&nbsp &nbsp Jeff Root
&nbsp &nbsp September 4, 2003

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The Sun and Planets to Scale &nbsp 1 pixel = 1000 kilometers The apparent brightnesses of the planets cover too wide a range to depict accurately. This picture gives an idea of their relative brightnesses due to differences in size, color, and reflectivity, but not due to distance from the Earth or Sun.

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If the Moon Were Only 1 Pixel - A tediously accurate map of the solar system

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You've now reached the outer edges of our own solar system

It would take you about 23 million years of continuous scrolling on this scale to get to the farthest regions of the observable universe, another 435,000,000,000,000,000,000,000 km
or 46 billion light years away.

We think we'll stop here.

Live long and prosper

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You've now reached the outer edges of our own solar system It would take you about 23 million years of continuous scrolling on this scale to get to the farthest regions of the observable universe, another 435,000,000,000,000,000,000,000 kmor 46 billion light years away. We think we'll stop here.

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StarTalk Radio Show by Neil deGrasse Tyson

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How much has space imaging furthered our understanding of the Universe? Neil deGrasse Tyson and comedian Chuck Nice learn the story of cameras on space probes like Voyager and Cassini and the exciting science of Saturn with planetary scientist Carolyn Porco.

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Overview Since 1998, NASA's Solar System Exploration hub has served as a real-time, living encyclopedia of the scientific exploration of our solar system. We provide reliable, accurate, up-to-date information about the planets, moons, asteroids, comets, and everything else in our solar system and the spacecraft that explore them.

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Online 3D simulation of the Solar System and night sky in real time - the Sun, planets, dwarf planets, comets, stars and constellations

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Earth is far from the only celestial body in the Solar System.

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Visualize orbits, relative positions and movements of the Solar System objects in an interactive 3D Solar System viewer and simulator.

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Observing Kepler's Laws of Orbital Motion at Work Kepler's laws show the effects of gravity on orbits. They apply to any object that orbits another: planets orbiting the Sun, moons orbiting a planet, spacecraft orbiting Earth.

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NASA's citizen science projects are collaborations between scientists and interested members of the public. Through these collaborations, volunteers (known as citizen scientists) have helped make thousands of important scientific discoveries. More than 410 NASA citizen scientists have been named as co-authors on refereed scientific publications. Want to work on some real NASA science?

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NASA's space shuttle fleet began setting records with its first launch on April 12, 1981 and continued to set high marks of achievement and endurance through 30 years of missions.

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NASA.gov brings you the latest images, videos and news from America’s space agency. Get the latest updates on NASA missions, watch NASA TV live, and learn about our quest to reveal the unknown and benefit all humankind.

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Editor's note: On the anniversary of the first launch of the Space Shuttle Discovery, we'll hear from Dr. Ellen R. Stofan, planetary geologist and the John and Adrienne Mars Director of the Smithsonian National Air and Space Museum, about a new 360 film on board the Shuttle that launched the Hubble Space Telescope.
Since the dawn of spaceflight, only a few hundred people have experienced space firsthand. But since the beginning, there have been moments that captured the world's imagination and challenged our collective Earth-bound perspective. Of the many orbital endeavors that have made headlines through the decades, one of the most enduring and prolific has been the Hubble Space Telescope.

The Hubble has been called one of the most important single scientific instruments of all time. The data it collected has deepened our understanding of the natural world-from the edge of our solar system to the age of the universe-and the images it has returned have brought the startling beauty of the cosmos to people around the world.

Today, on the 34th anniversary of the Space Shuttle Discovery's maiden voyage, the Smithsonian's National Air and Space Museum and Google Arts & Culture have teamed up to bring visitors into the orbiter like never before. Two of the astronauts who helped deliver Hubble to orbit as part of STS-31-Maj Gen Charlie Bolden and Dr. Kathy Sullivan-take us on a 360 journey inside Discovery at the Museum's Steven F. Udvar-Hazy Center.

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Step aboard Discovery with virtual reality

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Editor's note: On the anniversary of the first launch of the Space Shuttle Discovery, we'll hear from Dr. Ellen R. Stofan, planetary geologist and the John and Adrienne Mars Director of the Smithsonian National Air and Space Museum, about a new 360 film on board the Shuttle that launched the Hubble Space Telescope.

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NASA.gov brings you images, videos and interactive features from the unique perspective of America’s space agency. Get the latest updates on NASA missions, subscribe to blogs, RSS feeds and podcasts, watch NASA TV live, or simply read about our mission to pioneer the future in space exploration, sc…

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NASA's year-long Twins Study compared identical twins - Scott and Mark Kelly - while Scott was in space and Mark was on Earth.

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International Space Station - Google Arts & Culture

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Google Arts & Culture features content from over 2000 leading museums and archives who have partnered with the Google Cultural Institute to bring the world's treasures online.

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FAIL

Successful docking is achieved when all green numbers are below 0.2 and your RATE is below -0.2 m/s. Play again and review the DOCKING TIPS to familiarize yourself with the interface and the goals of the mission.

SUCCESS

You have successfully docked with the International Space Station. Follow SpaceX and NASA on Twitter for updates on the Commercial Crew Program as we prepare to send astronauts to the International Space Station from American soil. Watch the following video to see the actual interface used by crew

This simulator will familiarize you with the controls of the actual interface used by NASA Astronauts to manually pilot the SpaceX Dragon 2 vehicle to the International Space Station. Successful docking is achieved when all green numbers in the center of the interface are below 0.2. Movement in space is slow and requires patience & precision.

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This simulator will familiarize you with the controls of the actual interface used by NASA Astronauts to manually pilot the SpaceX Dragon 2 vehicle to the International Space Station.

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My colleagues and I just 3D-printed a ratcheting socket wrench on the International Space Station by typing some commands on our computer in California.

We had overheard ISS Commander Barry Wilmore (who goes by "Butch") mention over the radio that he needed one, so we designed one in CAD and sent it up to him faster than a rocket ever could have. This is the first time we've ever "emailed" hardware to space.

We founded Made In Space, Inc. to design and build the first 3D printer for space. Our first printer was launched to the space station in September, and it printed its first object in November.

The socket wrench we just manufactured is the first object we designed on the ground and sent digitally to space, on the fly. It also marks the end of our first experiment-a sequence of 21 prints that together make up the first tools and objects ever manufactured off the surface of the Earth. (The other 20 objects were designed before the printer flew to the space station.)

These first prints will be brought down to Earth for examination, where they will be compared to identical objects manufactured on the ground. We will use them to characterize the effects of long-term microgravity on our 3D-printing process, so that we can model and predict the performance of objects that we manufacture in space in the future.

So, how do we "email" hardware to space?

1. We design the part in CAD (usually Autodesk Inventor), and convert it into a format ready for the 3D printer called G-code.

2. We send it to NASA from our office in Moffett Field, CA, using a combination of in-house and NASA software.

3. NASA transmits it to the space station, by way of the Huntsville Operations Support Center, which links developers and researchers on the ground with their payloads on ISS.

4. The code for the part is received by the 3D printer, which is located in the Microgravity Science Glovebox in the Columbus laboratory module, where the object is manufactured layer by layer.

5. An astronaut removes the object from the printer.

Because it's a lot faster to send digital data (which can travel at the speed of light) to space than it is to send physical objects (which involves waiting months to years for a rocket), it makes more sense to 3D-print things in space, when we can, instead of launching them.

On the ISS this type of technology translates to lower costs for experiments, faster design iteration, and a safer, better experience for the crew members, who can use it to replace broken parts or create new tools on demand. But what I'm really excited about is the impact this could have on human space exploration beyond Earth orbit.

When we do set up the first human colonies on the moon, Mars and beyond, we won't use rockets to bring along everything we need. We'll build what we need there, when we need it.

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My colleagues and I just 3D-printed a ratcheting socket wrench on the International Space Station by typing some commands on our computer in California. We had overheard ISS Commander Barry Wilmore...

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The Cold War between the United States and former Soviet Union gave birth to the space race and an unprecedented program of scientific exploration. The Soviets sent the first person into space on April 12, 1961. In response, President John F. Kennedy challenged our nation "to achieving the goal, before this decade is out, of landing a man on the Moon and returning him safely to earth." It took eight years and three NASA programs -- Mercury, Gemini and Apollo - but the United States got to the moon.

Apollo 11 astronaut Buzz Aldrin on the Moon. Look for Neil Armstrong reflected in Aldrin's visor. During the following three-and-a-half years, 10 astronauts followed in their footsteps.
Image Credit: NASA

Project Mercury

Project Mercury, the first U.S. program to put humans in space, made 25 flights, six of which carried astronauts between 1961 and 1963. The objectives of the program were: to orbit a human spacecraft around Earth, to investigate a person's ability to function in space, and to recover both the astronaut and spacecraft safely. More than 2 million people from government agencies and the aerospace industry combined their skills, initiative and experience to make the project possible. Mercury showed that humans could function for periods up to 34 hours of weightless flight.

Mercury Astronauts
Image Credit: NASA
Mercury astronauts, the "Original Seven." On April 9, 1959, NASA introduced its first astronaut class. Front row, left to right: Wally Schirra, Deke Slayton, John Glenn, Scott Carpenter; back row, Alan Shepard, Gus Grissom, and Gordon Cooper.

The Gemini Program

The Gemini program primarily tested equipment and mission procedures and trained astronauts and ground crews for future Apollo missions to the Moon. The program's main goals were: to test an astronaut's ability to fly long duration flights (14 days); to understand how a spacecraft could rendezvous and dock with another vehicle in Earth orbit; to perfect re-entry landing methods; and to further understand the effects of longer spaceflights on astronauts. NASA selected "Gemini" because the word is Latin for "twins," and the Gemini was a capsule built for two.

Spacewalk
Image Credit: NASA
Gemini IV spacewalk, June 3, 1965. NASA astronaut Ed White became the first American to walk in space.

The Apollo Program

Exactly eight years, one month and 26 days after President Kennedy challenged Americans to reach for the Moon, Project Apollo landed the first humans on the lunar surface and returned them safely to Earth. The Apollo program also developed technology to meet other national interests in space, conducted scientific exploration of the Moon, and developed humanity's capability to work in the lunar environment.

The ascent stage of the Apollo 11 lunar module approaching the command module for docking before the crew returned to Earth. Image Credit: NASA

The Apollo program was hit by tragedy as the first crew prepared to fly. On Jan. 27, 1967, fire swept through the Apollo 1 command module during a preflight test on the Cape Kennedy launch pad. Astronauts Gus Grissom, Ed White, and Roger Chaffee lost their lives. NASA was not deterred, but rather changed how things were done to ensure the safety and success of future missions.
Image Credit: NASA Image Credit: NASA
Apollo 13
Image Credit: NASA
A makeshift arrangement of equipment, parts and duct tape on the Apollo 13 Lunar Module (LM) saved the crew's lives after an oxygen tank explosion in the Service Module left them with the LM to use as a "lifeboat." Using materials only found on the spacecraft, NASA engineers on the ground designed and tested a system that removed carbon dioxide from the LM; the Apollo 13 crew then made the system onboard, April 17, 1970, and returned safely to Earth.

Skylab

In 1973, Skylab expeditions paved the way for the International Space Station. The four, windmill-like solar arrays were attached to the Apollo Telescope Mount. Observations of the Sun were one of this space lab program's primary achievements.

Apollo Soyuz Test Project
Image Credit: NASA
In the 1970s, U.S.-Soviet political tensions that had accelerated the space race began to thaw. Competition gave way to cooperation between the two nations with the Apollo-Soyuz Test Project. International collaboration among many nations would become the norm during the space shuttle era and current cooperation in human spaceflight with the International Space Station. These partnerships have taught us more about the universe, improved our lives at home, and expanded the possibilities for future exploration into deep space.

Handshake
Image Credit: NASA
Astronaut Tom Stafford (foreground) and cosmonaut Alexei Leonov make their historic handshake in space on July 17, 1975. The Apollo-Soyuz Test Project docked together U.S. and Soviet spacecraft and paved the way toward international partnerships in space.

Space Shuttle Era

Over 30 years, NASA's space shuttle fleet-Columbia, Challenger, Discovery, Atlantis and Endeavour-flew 135 missions and carried 355 different people to space. Humanity's first reusable spacecraft, the space shuttle carried people into orbit repeatedly; launched, recovered and repaired satellites; conducted cutting-edge research; and built the largest structure in space, the International Space Station. The space shuttle pushed the bounds of discovery ever farther, requiring not only advanced technologies but also the tremendous efforts of thousands of civil servants and contractors throughout NASA's field centers and across the nation. Tragically, NASA lost two crews of seven in the 1986 Challenger accident and the 2003 Columbia accident.

Space Shuttle Columbia, the world's first reusable space vehicle, landing at NASA's Dryden Flight Research Center (now NASA's Armstrong Flight Research Center) at Edwards Air Force Base, California, April 14, 1981. Image Credit: NASA

Space Station Era

The International Space Station is a model for global cooperation and scientific advancements that is enabling growth of private industry in low-Earth orbit and development of new technologies to advance human space exploration. Built between 1998 and 2011, the space station has housed humans continuously since Nov. 2, 2000. Because molecules and cells behave differently in space, research in microgravity helps advance scientific knowledge. The space station is a U.S. National Laboratory, which the Center for the Advancement of Science in Space (CASIS) manages for research investigations that improve life on Earth. NASA has contracted with commercial companies SpaceX, Orbital ATK, and Sierra Nevada Corporation to deliver science investigations, cargo, and supplies to the crews living in space, and soon Boeing and SpaceX will transport astronauts to and from the station.

This picture of the International Space Station was photographed from the space shuttle Atlantis as the orbiting complex and the shuttle performed their relative separation in the early hours of July 19, 2011 Image Credit: NASA

Spot the Station
Image Credit: NASA
Nighttime view of the eastern U.S. and Canada from the International Space Station. You can see the station too. Go to Spot the Station and sign up for text and email updates of sighting opportunities.

National Aeronautics and Space Administration

NASA Official: Brian Dunbar

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NASA.gov brings you the latest images, videos and news from America's space agency. Get the latest updates on NASA missions, watch NASA TV live, and learn about our quest to reveal the unknown and benefit all humankind.

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The electromagnetic (EM) spectrum is the range of all types of EM radiation. Radiation is energy that travels and spreads out as it goes – the visible light that comes from a lamp in your house and the radio waves that come from a radio station are two types of electromagnetic radiation. The other types of EM radiation that make up the electromagnetic spectrum are microwaves, infrared light, ultraviolet light, X-rays and gamma-rays.

You know more about the electromagnetic spectrum than you may think. The image below shows where you might encounter each portion of the EM spectrum in your day-to-day life.

Is a radio wave the same as a gamma ray?

Are radio waves completely different physical objects than gamma-rays? They are produced in different processes and are detected in different ways, but they are not fundamentally different. Radio waves, gamma-rays, visible light, and all the other parts of the electromagnetic spectrum are electromagnetic radiation.

Electromagnetic radiation can be described in terms of a stream of mass-less particles, called photons, each traveling in a wave-like pattern at the speed of light. Each photon contains a certain amount of energy. The different types of radiation are defined by the the amount of energy found in the photons. Radio waves have photons with low energies, microwave photons have a little more energy than radio waves, infrared photons have still more, then visible, ultraviolet, X-rays, and, the most energetic of all, gamma-rays.

Measuring electromagnetic radiation

Electromagnetic radiation can be expressed in terms of energy, wavelength, or frequency. Frequency is measured in cycles per second, or Hertz. Wavelength is measured in meters. Energy is measured in electron volts. Each of these three quantities for describing EM radiation are related to each other in a precise mathematical way. But why have three ways of describing things, each with a different set of physical units?

The short answer is that scientists don't like to use numbers any bigger or smaller than they have to. It is much easier to say or write "two kilometers" than "two thousand meters." Generally, scientists use whatever units are easiest for the type of EM radiation they work with.

Astronomers who study radio waves tend to use wavelengths or frequencies. Most of the radio part of the EM spectrum falls in the range from about 1 cm to 1 km, which is 30 gigahertz (GHz) to 300 kilohertz (kHz) in frequencies. The radio is a very broad part of the EM spectrum.

Infrared and optical astronomers generally use wavelength. Infrared astronomers use microns (millionths of a meter) for wavelengths, so their part of the EM spectrum falls in the range of 1 to 100 microns. Optical astronomers use both angstroms (0.00000001 cm, or ) and nanometers (0.0000001 cm, or ). Using nanometers, violet, blue, green, yellow, orange, and red light have wavelengths between 400 and 700 nanometers. (This range is just a tiny part of the entire EM spectrum, so the light our eyes can see is just a little fraction of all the EM radiation around us.)

The wavelengths of ultraviolet, X-ray, and gamma-ray regions of the EM spectrum are very small. Instead of using wavelengths, astronomers that study these portions of the EM spectrum usually refer to these photons by their energies, measured in electron volts (eV). Ultraviolet radiation falls in the range from a few electron volts to about 100 eV. X-ray photons have energies in the range 100 eV to 100,000 eV (or 100 keV). Gamma-rays then are all the photons with energies greater than 100 keV.

Show me a chart of the wavelength, frequency, and energy regimes of the spectrum

Why do we put telescopes in orbit?

Most electromagnetic radiation from space is unable to reach the surface of the Earth. Radio frequencies, visible light and some ultraviolet light makes it to sea level. Astronomers can observe some infrared wavelengths by putting telescopes on mountain tops. Balloon experiments can reach 35 km above the surface and can operate for months. Rocket flights can take instruments all the way above the Earth's atmosphere, but only for a few minutes before they fall back to Earth.

For long-term observations, however, it is best to have your detector on an orbiting satellite and get above it all!

Updated: March 2013

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The electromagnetic (EM) spectrum is the range of all types of EM radiation. Radiation is energy that travels and spreads out as it goes - the visible light that comes from a lamp in your house and the radio waves that come from a radio station are two types of electromagnetic radiation.

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Space

There are nearly 6,000 satellites circling the Earth, but only 40% are operational. Image: Unsplash/Space X

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Global Agenda

The Agenda Weekly

A weekly update of the most important issues driving the global agenda

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Who owns our orbit: Just how many satellites are there in space?

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Satellites are a vital part of our infrastructure, helping us to use GPS, access the internet and support studies of the Earth. There were 2,666 operational satellites in April 2020.

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What's Up in the Solar System diagram by Olaf Frohn (updated for July 2019) A diagram, updated once a month, of active space missions traveling beyond Earth orbit. Contains links to past diagrams.

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What's Up in the Solar System diagram by Olaf Frohn (updated for July...

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A diagram, updated once a month, of active space missions traveling beyond Earth orbit. Contains links to past diagrams.

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Robotic spacecraft are specially designed and constructed systems that can function in specific hostile environments. Their complexity and capabilities vary greatly and their purposes are diverse. To make some sense of all these variables, this chapter arbitrarily designates eight broad classes of robotic spacecraft according to the missions the spacecraft are intended to perform:

1. Flyby spacecraft
2. Orbiter spacecraft
3. Atmospheric spacecraft
4. Lander spacecraft
5. Rover spacecraft
6. Penetrator spacecraft
7. Observatory spacecraft
8. Communications spacecraft

We illustrate these eight classes by offering one prime example of each pictured on this page and, in most cases, some additional linked examples. Be sure to select and read each prime example, plus several additional links. The JPL public website has an up-to-date listing of all past, current, future and proposed JPL robotic spacecraft missions. Spacecraft that carry human occupants are not considered here.

(1) Flyby Spacecraft

Flyby spacecraft conducted the initial reconnaissance phase of solar system exploration. They follow a continuous solar orbit or escape trajectory, never to be captured into a planetary orbit. They must have the capability of using their instruments to observe targets they pass. Ideally, they can pan to compensate for the target's apparent motion in optical instruments' field of view. They must downlink data to Earth, storing data onboard during the periods when their antennas are off Earthpoint. They must be able to survive long periods of interplanetary cruise. Flyby spacecraft may be designed to be stabilized in 3 axes using thrusters or reaction wheels or to spin continuously for stabilization. Our prime example of the flyby spacecraft category is Voyager 2, which conducted encounters in the Jupiter, Saturn, Uranus, and Neptune systems. Click the Voyager image for details of the twin Voyager 1 and 2 spacecraft. Other examples of flyby spacecraft include:

(2) Orbiter Spacecraft

A spacecraft designed to travel to a distant planet and enter into orbit about it must carry with it a substantial propulsive capability to decelerate it at the right moment to achieve orbit insertion. It has to be designed to live with the fact that solar occultations will occur, wherein the planet shadows the spacecraft, cutting off any solar panels' production of electrical power and subjecting the vehicle to extreme thermal variation. Earth occultations will also occur, cutting off uplink and downlink communications with Earth. Orbiter spacecraft are carrying out the second phase of solar system exploration, following up the initial reconnaissance with in-depth study of each of the planets. These include Magellan, Galileo, Mars Global Surveyor, and Cassini. Our prime example of the orbiter spacecraft category is Galileo which entered orbit about Jupiter in 1995 to carry out a highly successful study of the Jovian system. Click the Galileo image for details of the Galileo spacecraft. Other examples of orbiter spacecraft include:

(3) Atmospheric Spacecraft

Atmospheric spacecraft are designed for a relatively short mission to collect data about the atmosphere of a planet or satellite. One typically has a limited complement of spacecraft subsystems. For example, an atmospheric spacecraft may have no need for propulsion subsystems or attitude and articulation control system subsystems at all. It does require an electric power supply, which may simply be batteries, and telecommunications equipment for tracking and data relay. Its scientific instruments may take direct measurements of an atmosphere's composition, temperature, pressure, density, cloud content and lightning.

Typically, atmospheric spacecraft are carried to their destination by another spacecraft. Galileo carried its atmospheric probe on an impact trajectory with Jupiter in 1995 and increased its spin rate to stabilize the probe's attitude for atmospheric entry. After probe release Galileo maneuvered to change from an impact trajectory to a Jupiter Orbit Insertion trajectory. An aeroshell protected the probe from the thousands of degrees of heat created by atmospheric friction during atmospheric entry, then parachutes deployed after the aeroshell was jettisoned. The probe completed its mission on battery power, and the orbiter relayed the data to Earth. The Pioneer 13 Venus Multiprobe Mission deployed four atmospheric probes that returned data directly to Earth during descent into the Venusian atmosphere in 1978.

Balloon packages are atmospheric probes designed for suspension from a buoyant gas bag to float and travel with the wind. The Soviet Vega 1 and Vega 2 missions to Comet Halley in 1986 deployed atmospheric balloons in Venus' atmosphere en route to the comet. DSN tracked the instrumented balloons to investigate winds in the Venusian atmosphere. (The Vega missions also deployed Venus landers.) While not currently funded, informal plans for other kinds of atmospheric spacecraft include battery powered instrumented airplanes and balloons for investigations in Mars' atmosphere.

Our prime example of the atmospheric spacecraft category is Huygens, which is being carried to Saturn's moon Titan by the Cassini spacecraft. Click the Huygens image for details of the Huygens spacecraft. Other examples of atmospheric spacecraft include:

(4) Lander Spacecraft

Lander spacecraft are designed to reach the surface of a planet and survive long enough to telemeter data back to Earth. Examples have been the highly successful Soviet Venera landers which survived the harsh conditions on Venus while carrying out chemical composition analyses of the rocks and relaying color images, JPL's Viking landers at Mars, and the Surveyor series of landers at Earth's moon, which carried out similar experiments. The Mars Pathfinder project, which landed on Mars on July 4, 1997, and deployed a rover, was intended to be the first in a series of landers on the surface of Mars at widely distributed locations to study the planet's atmosphere, interior, and soil. A system of actively-cooled, long-lived Venus landers designed for seismology investigations, is being envisioned for a possible future mission.

Our prime example of the lander spacecraft category is Mars Pathfinder. Click the Pathfinder image for details of the Pathfinder spacecraft. Other examples of lander spacecraft include:

(5) Penetrator Spacecraft

Surface penetrators have been designed for entering the surface of a body, such as a comet, surviving an impact of hundreds of Gs, measuring, and telemetering the properties of the penetrated surface. As of November 2000, no Penetrator spacecraft have been successfully operated. Penetrator data would typically be telemetered to an orbiter craft for re-transmission to Earth. The Comet Rendezvous / Asteroid Flyby (CRAF) mission included a cometary penetrator, but the mission was cancelled in 1992 due to budget constraints.

Our prime example of a penetrator spacecraft is the twin Deep Space 2 penetrators which piggybacked to Mars aboard the Mars Polar Lander and were to slam into Martian soil December 3, 1999. They were never heard from. Click the Deep Space 2 image for details of the penetrator spacecraft. Another example of penetrator spacecraft include:

(6) Rover Spacecraft

Electrically-powered rover spacecraft are being designed and tested by JPL as part of Mars exploration effort. The Mars Pathfinder project included a small, highly successful mobile system referred to as a micro-rover by the name of Sojourner. Mars rovers are also being developed by Russia with a measure of support from The Planetary Society. Rover craft need to be semi-autonomous. They are steerable from Earth. Their purposes range from taking images and soil analyses to collecting samples for return to Earth.

Our prime example of a rover spacecraft is of course the famous Sojourner Rover, shown here in an image from the surface of Mars. Click the Sojourner image for details of the rover spacecraft.

(7) Observatory Spacecraft

An observatory spacecraft does not travel to a destination to explore it. Instead, it occupies an Earth orbit or a solar orbit from where it can observe distant targets free of the obscuring and blurring effects of Earth's atmosphere.

NASA's Great Observatories program studies the universe at wavelengths from visible light to gamma-rays. The program includes four Observatory Spacecraft: the familiar Hubble Space Telescope (HST), the Chandra X-Ray Observatory (CXO -- previously known as AXAF), the Compton Gamma Ray Observatory (GRO), and the Space Infrared Telescope Facility (SIRTF).

The HST is still operating as of November 2000. GRO has completed its mission and was de-orbited in June 2000. CXO was launched in July 1999 and continues to operate. SIRTF is set to launch in January 2003. In the coming decades many new kinds of observatory spacecraft will be deployed to take advantage of the tremendous gains available from operating in space.

Our prime example of an observatory spacecraft is the JPL SIRTF Project. Click the SIRTF image for details of the observatory spacecraft. Other examples of observatory spacecraft include:

(8) Communications Spacecraft

Communications spacecraft are abundant in Earth orbit, but they are largely incidental to JPL's missions. The Deep Space Network's Ground Communications Facility does make use of Earth-orbiting communications spacecraft to transfer data among its sites in Spain, Australia, California, and JPL.

In the future, communications spacecraft may be deployed at Mars, Venus, or other planets to communicate with orbiters, rovers, penetrators, and atmospheric spacecraft operating in their vicinity. Their purpose would be to augment the Deep Space Network's capabilities to communicate with the resident spacecraft. None are in place as of November, 2000. This concept is revisited in Chapter 18. The communications spacecraft example offered here is NASA's Tracking and Data Relay Satellite System, TDRSS. Click the TDRSS image for details of this communications spacecraft.

For Further Browsing

Here is a list of virtually every lunar and planetary mission ever flown or attempted by any nation, and those on schedule for future launch. The list is arranged by launch date, and each entry is linked to a page of facts about the mission.

Excerpt from Basics of Space Flight

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NASA - National Aeronautics and Space Administration

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Robotic spacecraft are specially designed and constructed systems that can function in specific hostile environments. Their complexity and capabilities vary greatly and their purposes are diverse. To make some sense of all these variables, this chapter arbitrarily designates eight broad classes of robotic spacecraft according to the missions the spacecraft are intended to perform: 1.

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We're going back to the Moon for scientific discovery, economic benefits, and inspiration for a new generation of explorers: the Artemis Generation. While maintaining American leadership in exploration, we will build a global alliance and explore deep space for the benefit of all.

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https://www.nasa.gov/wp-content/uploads/static/artemis/Artemis is the name of NASA's program to return astronauts to the lunar surface. We are going forward to the Moon to stay.

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Webb Image Release- Webb Space Telescope GSFC/NASA

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The Latest NASA Released Webb Image is featured on this page. The James Webb Space Telescope's revolutionary technology will study every phase of cosmic history-from within our solar system to the most distant observable galaxies in the early universe.

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NASA.gov brings you the latest images, videos and news from America's space agency. Get the latest updates on NASA missions, watch NASA TV live, and learn about our quest to reveal the unknown and benefit all humankind.

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NASA’s first global SAR mission, in partnership with ISRO, providing data for studying hazards, changes in glaciers and ice sheets, and global environmental change.

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Earth’s first mission to conduct detailed reconnaissance of Jupiter’s moon, Europa. NASA’s Europa Clipper will determine if this ocean world has environments suitable for life to exist.

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SWOT: NASA's first global survey of Earth's surface water, providing data for clean air and water, extreme events, and long-term environmental changes

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united nations office outer space affairs un

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Regional Centres for Space Science and Technology Education

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We celebrate NASA’s first 60 years of achievement

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The Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer (SPHEREx) mission will provide the first all-sky spectral survey. Over a two-year planned mission, the SPHEREx Observatory will collect data on more than 300 million galaxies along with more than 100 million stars in the Milky Way in order to explore the origins of the universe.

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Learn how and why we explore our solar system and beyond with space exploration missions, and find out how you can get involved.

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NASA.gov brings you the latest images, videos and news from America's space agency. Get the latest updates on NASA missions, watch NASA TV live, and learn about our quest to reveal the unknown and benefit all humankind.

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Extra dimensions, gravitons, and tiny black holes

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At CERN, we probe the fundamental structure of particles that make up everything around us. We do so using the world's largest and most complex scientific instruments.

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What lies beyond all we can see? The question may seem unanswerable. Nevertheless, some cosmologists have a response: Our universe is a swelling bubble. Outside it, more bubble universes exist, all immersed in an eternally expanding and energized sea - the multiverse.

The idea is polarizing. Some physicists embrace the multiverse to explain why our bubble looks so special (only certain bubbles can host life), while others reject the theory for making no testable predictions (since it predicts all conceivable universes). But some researchers expect that they just haven't been clever enough to work out the precise consequences of the theory yet.

Now, various teams are developing new ways to infer exactly how the multiverse bubbles and what happens when those bubble universes collide.

"It's a long shot," said Jonathan Braden, a cosmologist at the University of Toronto who is involved in the effort, but, he said, it's a search for evidence "for something you thought you could never test."

The multiverse hypothesis sprang from efforts to understand our own universe's birth. In the large-scale structure of the universe, theorists see signs of an explosive growth spurt during the cosmos's infancy. In the early 1980s, as physicists investigated how space might have started - and stopped - inflating, an unsettling picture emerged. The researchers realized that while space may have stopped inflating here (in our bubble universe) and there (in other bubbles), quantum effects should continue to inflate most of space, an idea known as eternal inflation.

The difference between bubble universes and their surroundings comes down to the energy of space itself. When space is as empty as possible and can't possibly lose more energy, it exists in what physicists call a "true" vacuum state. Think of a ball lying on the floor - it can't fall any further. But systems can also have "false" vacuum states. Imagine a ball in a bowl on a table. The ball can roll around a bit while more or less staying put. But a large enough jolt will land it on the floor - in the true vacuum.

In the cosmological context, space can get similarly stuck in a false vacuum state. A speck of false vacuum will occasionally relax into true vacuum (likely through a random quantum event), and this true vacuum will balloon outward as a swelling bubble, feasting on the false vacuum's excess energy, in a process called false vacuum decay. It's this process that may have started our cosmos with a bang. "A vacuum bubble could have been the first event in the history of our universe," said Hiranya Peiris, a cosmologist at University College London.

But physicists struggle mightily to predict how vacuum bubbles behave. A bubble's future depends on countless minute details that add up. Bubbles also change rapidly - their walls approach the speed of light as they fly outward - and feature quantum mechanical randomness and waviness. Different assumptions about these processes give conflicting predictions, with no way to tell which ones might resemble reality. It's as though "you've taken a lot of things that are just very hard for physicists to deal with and mushed them all together and said, 'Go ahead and figure out what's going on,'" Braden said.

Since they can't prod actual vacuum bubbles in the multiverse, physicists have sought digital and physical analogs of them.

One group recently coaxed vacuum bubble-like behavior out of a simple simulation. The researchers, including John Preskill, a prominent theoretical physicist at the California Institute of Technology, started with "the [most] baby version of this problem that you can think of," as co-author Ashley Milsted put it: a line of about 1,000 digital arrows that could point up or down. The place where a string of mainly up arrows met a string of largely down arrows marked a bubble wall, and by flipping arrows, the researchers could make bubble walls move and collide. In certain circumstances, this model perfectly mimics the behavior of more complicated systems in nature. The researchers hoped to use it to simulate false vacuum decay and bubble collisions.

At first the simple setup didn't act realistically. When bubble walls crashed together, they rebounded perfectly, with none of the expected intricate reverberations or outflows of particles (in the form of flipped arrows rippling down the line). But after adding some mathematical flourishes, the team saw colliding walls that spewed out energetic particles - with more particles appearing as the collisions grew more violent.

But the results, which appeared in a preprint in December, foreshadow a dead end in this problem for traditional computation. The researchers found that as the resulting particles mingle, they become "entangled," entering a shared quantum state. Their state grows exponentially more complicated with each additional particle, choking simulations on even the mightiest supercomputers.

For that reason, the researchers say that further discoveries about bubble behavior might have to wait for mature quantum computers - devices whose computational elements (qubits) can handle quantum entanglement because they experience it firsthand.

Meanwhile, other researchers hope to get nature to do the math for them.

Michael Spannowsky and Steven Abel, physicists at Durham University in the United Kingdom, believe they can sidestep the tricky calculations by using an apparatus that plays by the same quantum rules that the vacuum does. "If you can encode your system on a device that's realized in nature, you don't have to calculate it," Spannowsky said. "It becomes more of an experiment than a theoretical prediction."

That device is known as a quantum annealer. A limited quantum computer, it specializes in solving optimization problems by letting qubits seek out the lowest-energy configuration available - a process not unlike false vacuum decay.

Using a commercial quantum annealer called D-Wave, Abel and Spannowsky programmed a string of about 200 qubits to emulate a quantum field with a higher- and a lower-energy state, analogous to a false vacuum and a true vacuum. They then let the system loose and watched how the former decayed into the latter - leading to the birth of a vacuum bubble.

The experiment, described in a preprint last June, merely verified known quantum effects and did not reveal anything new about vacuum decay. But the researchers hope to eventually use D-Wave to tiptoe beyond current theoretical predictions.

A third approach aims to leave the computers behind and blow bubbles directly.

Quantum bubbles that inflate at nearly light speed aren't easy to come by, but in 2014, physicists in Australia and New Zealand proposed a way to make some in the lab using an exotic state of matter known as a Bose-Einstein condensate (BEC). When cooled to nearly absolute zero, a thin cloud of gas can condense into a BEC, whose uncommon quantum mechanical properties include the ability to interfere with another BEC, much as two lasers can interfere. If two condensates interfere in just the right way, the group predicted, experimentalists should be able to capture direct images of bubbles forming in the condensate - ones that act similarly to the putative bubbles of the multiverse.

"Because it's an experiment, it contains by definition all the physics that nature wants to put in it including quantum effects and classical effects," Peiris said.

Peiris leads a team of physicists studying how to steady the condensate blend against collapse from unrelated effects. After years of work, she and her colleagues are finally ready to set up a prototype experiment, and they hope to be blowing condensate bubbles in the next few years.

If all goes well, they'll answer two questions: the rate at which bubbles form, and how the inflation of one bubble changes the odds that another bubble will inflate nearby. These queries can't even be formulated with current mathematics, said Braden, who contributed to the theoretical groundwork for the experiment.

That information will help cosmologists like Braden and Peiris to calculate exactly how a whack from a neighboring bubble universe in the distant past might have set our cosmos quivering. One likely scar from such an encounter would be a circular cold spot in the sky, which Peiris and others have searched for and not found. But other details - such as whether the collision also produces gravitational waves - depend on unknown bubble specifics.

If the multiverse is just a mirage, physics may still benefit from the bounty of tools being developed to uncover it. To understand the multiverse is to understand the physics of space, which is everywhere.

False vacuum decay "seems like a ubiquitous feature of physics," Peiris said, and "I personally don't believe pencil-and-paper theory calculations are going to get us there."

This article was reprinted on Wired.com and in Spanish at Investigacionyciencia.es.

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Physicists Study How Universes Might Bubble Up and Collide

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Since they can't prod actual universes as they inflate and bump into each other in the hypothetical multiverse, physicists are studying digital and physical analogs of the process.

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Credit: Gianni Martire (Applied Physics)

A pair of researchers at Applied Physics has created what they describe as the first general model for a warp drive, a model for a space craft that could travel faster than the speed of light, without actually breaking the laws of physics. Alexey Bobrick, and Gianni Martire have written a paper describing their ideas for a warp drive and have published it in IOP's Classical and Quantum Gravity.

Back in the '60s, television viewers became familiar with the idea of a warp drive courtesy of the television show "Star Trek." When the crew needed to get somewhere fast, Captain Kirk gave his famous command ("Mr. Sulu, execute"), and the ship was pushed swiftly to another distant destination. Physicists have scoffed at the idea of a real warp drive, however, because it suggests travel faster than light. But in actuality, as the name of the drive suggests, such an engine did not actually push the craft faster than the speed of light; instead, it simply warped space time in a way that allowed for using a shortcut. Imagine a napkin. If you had to traverse its entire surface, it would take a certain amount of time. But what if you folded the napkin in half and moved through and across the folds? You could get to your destination in almost no time. In this new effort, the researchers have taken a previous idea based on warping space-time a step further to create a model for a warp drive that they believe could be feasible in the future.

Bobrick and Martire start with the idea of an Alcubierre warp drive, a concept developed by Miguel Alcubierre in 1994-he envisioned it as spacecraft that could contract space time in front of the vehicle while expanding it behind the craft. But such a craft would require a massive amount of negative energy, which would not be feasible for a real spacecraft. Bobrick and Martire suggest instead that a massive gravitational force could be used to bend space time. The trick is finding a way to compress a planet-sized mass to a manageable spacecraft-module size in order to use its gravity. Because of the implied difficulties, a warp drive created from the model developed by the researchers could not be built today, but it does suggest that someday it might be possible.

More information: Alexey Bobrick et al. Introducing physical warp drives, Classical and Quantum Gravity (2021). DOI: 10.1088/1361-6382/abdf6e

On Arxiv: arxiv.org/abs/2102.06824

© 2021 Science X Network

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A potential model for a real physical warp drive

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A pair of researchers at Applied Physics has created what they describe as the first general model for a warp drive, a model for a space craft that could travel faster than the speed of light, without actually breaking the laws of physics.

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The 12 Strangest Objects in the Universe

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A gallery taking a look at some of the strangest objects in the universe.

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Drag Earth or the Moon to change the time.

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Moon.nasa.gov is NASA's deep dive resource for lunar exploration from astronauts to robots.

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Have you ever wondered when the next full moon will be? How about the first quarter moon? Now you can have all the dates and times for all the moon phases for the year at your fingertips by building your own moon phases calendar and calculator!

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Student Project: Make a Moon Phases Calendar and Calculator - New for 2024 | NASA/JPL Edu

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Like a decoder wheel for the Moon, this calendar will show you where and when to see the Moon and every moon phase throughout the year. 2024 calendar now available!

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The Moon's current phase for today and tonight is a Waxing Gibbous phase. Visible through most of the night sky setting a few hours before sunrise. This phase is when the moon is more than 50% illuminated but not yet a Full Moon. The phase lasts about 7 days with the moon becoming more illuminated each day until the Full Moon. During a Waxing Gibbous the moon rises in the east in mid-afternoon and is high in the eastern sky at sunset. The word Gibbous first appeared in the 14th century and has its roots in the Latin word "gibbosus" meaning humpbacked.

Visit the July 2023 Moon Phases Calendar to see all the daily moon phase for this month.

Today's Waxing Gibbous Phase

The Waxing Gibbous on July 31 has an illumination of 98%. This is the percentage of the Moon illuminated by the Sun. The illumination is constantly changing and can vary up to 10% a day. On July 31 the Moon is 13.28 days old. This refers to how many days it has been since the last New Moon. It takes 29.53 days for the Moon to orbit the Earth and go through the lunar cycle of all 8 Moon phases.

The 8 Lunar Phases

There are 8 lunar phases the Moon goes through in its 29.53 days lunar cycle. The 4 major Moon phases are Full Moon, New Moon, First Quarter and Last Quarter. Between these major phases, there are 4 minor ones: the Waxing Crescent, Waxing Gibbous, Waning Gibbous and Waning Crescent. For more info on the Moon Cycle and on each phase check out Wikipedia Lunar Phase page.

TODAY'S MOON PHASE

Phase Details for - July 31

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Moon Phase for today and tonight with current lunar phase, illumination percentage and Moons age. Find out what the Moon Phase is on any other day of the year

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High tides and low tides are caused by the moon. The moon's gravitational pull generates something called the tidal force. The tidal force causes Earth-and its water-to bulge out on the side closest to the moon and the side farthest from the moon. These bulges of water are high tides.

As the Earth rotates, your region of Earth passes through both of these bulges each day. When you're in one of the bulges, you experience a high tide. When you're not in one of the bulges, you experience a low tide. This cycle of two high tides and two low tides occurs most days on most of the coastlines of the world.

More About Tides

Tides are really all about gravity, and when we're talking about the daily tides, it's the moon's gravity that's causing them.

As Earth rotates, the moon's gravity pulls on different parts of our planet. Even though the moon only has about 1/100th the mass of Earth, since it's so close to us, it has enough gravity to move things around. The moon's gravity even pulls on the land, but not enough for anyone to tell (unless they use special, really precise instruments).

When the moon's gravity pulls on the water in the oceans, however, someone's bound to notice. Water has a much easier time moving around, and the water wants to bulge in the direction of the moon. This is called the tidal force.

Because of the tidal force, the water on the side of the moon always wants to bulge out toward the moon. This bulge is what we call a high tide. As your part of the Earth rotates into this bulge of water, you might experience a high tide.

One thing to note, however, is that this is just an explanation of the tidal force-not the actual tides. In real life, the Earth isn't a global ocean, covered in an even layer of water. There are seven continents, and that land gets in the way. The continents prevent the water from perfectly following the moon's pull. That's why in some places, the difference between high and low tide isn't very big, and in other places, the difference is drastic.

That explains the first high tide each day, but what about the second high tide?

The ocean also bulges out on the side of Earth opposite the moon.

Wait, what?

If the moon's gravity is pulling the oceans toward it, how can the ocean also bulge on the side of Earth away from the moon? It does seem a little weird. It's all because the tidal force is a differential force-meaning that it comes from differences in gravity over Earth's surface. Here's how it works:

On the side of Earth that is directly facing the moon, the moon's gravitational pull is the strongest. The water on that side is pulled strongly in the direction of the moon.

On the side of Earth farthest from the moon, the moon's gravitational pull is at its weakest. At the center of Earth is approximately the average of the moon's gravitational pull on the whole planet.

To get the tidal force-the force that causes the tides-we subtract this average gravitational pull on Earth from the gravitational pull at each location on Earth.

Tidal force =
moon's gravitational pull in a specific location on Earth -
moon's average gravitational pull over the whole Earth

The result of the tidal force is a stretching and squashing of Earth. This is what causes the two tidal bulges.

These two bulges explain why in one day there are two high tides and two low tides, as the Earth's surface rotates through each of the bulges once a day.

Does anything else affect tides?

The Sun causes tides just like the moon does, although they are somewhat smaller. When the earth, moon, and Sun line up-which happens at times of full moon or new moon-the lunar and solar tides reinforce each other, leading to more extreme tides, called spring tides. When lunar and solar tides act against each other, the result is unusually small tides, called neap tides. There is a new moon or a full moon about every two weeks, so that's how often we see large spring tides.

Wind and weather patterns also can affect water level. Strong offshore winds can move water away from coastlines, exaggerating low tides. Onshore winds can push water onto the shore, making low tides much less noticeable.

High-pressure weather systems can push down sea levels, leading to lower tides. Low-pressure systems-brought on by strong storms and hurricanes-can cause tides than are much higher than predicted, so watch out!

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Tides are a complicated dance between gravity and inertia.

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A spring tide is a common historical term that has nothing to do with the season of spring. Rather, the term is derived from the concept of the tide "springing forth." Spring tides occur twice each lunar month all year long without regard to the season. Neap tides, which also occur twice a month, happen when the sun and moon are at right angles to each other.

Tides are long-period waves that roll around the planet as the ocean is "pulled" back and forth by the gravitational pull of the moon and the sun as these bodies interact with the Earth in their monthly and yearly orbits.

During full or new moons-which occur when the Earth, sun, and moon are nearly in alignment-average tidal ranges are slightly larger. This occurs twice each month. The moon appears new (dark) when it is directly between the Earth and the sun. The moon appears full when the Earth is between the moon and the sun. In both cases, the gravitational pull of the sun is "added" to the gravitational pull of the moon on Earth, causing the oceans to bulge a bit more than usual. This means that high tides are a little higher and low tides are a little lower than average.

These are called spring tides, a common historical term that has nothing to do with the season of spring. Rather, the term is derived from the concept of the tide "springing forth." Spring tides occur twice each lunar month all year long, without regard to the season.

Seven days after a spring tide, the sun and moon are at right angles to each other. When this happens, the bulge of the ocean caused by the sun partially cancels out the bulge of the ocean caused by the moon. This produces moderate tides known as neap tides, meaning that high tides are a little lower and low tides are a little higher than average. Neap tides occur during the first and third quarter moon, when the moon appears "half full."

NOAA's tide and tidal current predictions take into account astronomical considerations due to the position of the moon and the sun.

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national oceanic and atmospheric administration

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Tides are long-period waves that roll around the planet as the ocean is "pulled" back and forth by the gravitational pull of the moon and the sun as these bodies interact with the Earth in their monthly and yearly orbits.

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Eclipse Information and Pictures below this post

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Eclipse Information and Pictures below this post

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If you do not wish to see pictures of lunar and/or solar eclipses do not scroll past this post.  There are links below about eclipses so this is a buffer before those links.

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This article is for students grades 5-8.

An eclipse occurs when one heavenly body such as a moon or planet moves into the shadow of another heavenly body. Let's learn about the two types of eclipses on Earth.

What is a Lunar Eclipse?

The Moon moves in an orbit around Earth. At the same time, Earth orbits the Sun. Sometimes Earth moves between the Sun and the Moon. When this happens, Earth blocks the sunlight that normally is reflected by the Moon. (This sunlight is what causes the Moon to shine.) Instead of light hitting the Moon's surface, Earth's shadow falls on the Moon. This is an eclipse of the Moon, or a lunar eclipse. A lunar eclipse can occur only when the Moon is full.

A lunar eclipse can be seen from Earth at night. There are two types of lunar eclipses:

1. Total lunar eclipse.

2. Partial lunar eclipse.

A total lunar eclipse occurs when the Moon and the Sun are on exact opposite sides of Earth. Although the Moon is in Earth's shadow, some sunlight reaches the Moon. The sunlight passes through Earth's atmosphere, which filters out most of the blue light. This makes the Moon appear red to people on Earth.

A partial lunar eclipse happens when part of the Moon enters Earth's shadow. In a partial eclipse, Earth's shadow appears very dark on the side of the Moon facing Earth. What people see from Earth during a partial lunar eclipse depends on how the Sun, Earth and Moon align.

A lunar eclipse usually lasts for a few hours. At least two partial lunar eclipses happen every year, but total lunar eclipses are rare. It is safe to look at a lunar eclipse.

What is a Solar Eclipse?

Sometimes when the Moon orbits Earth, the Moon moves between the Sun and Earth. When this happens, the Moon blocks the light of the Sun from reaching Earth. This causes an eclipse of the Sun, or a solar eclipse. During a solar eclipse, the Moon casts a shadow onto Earth.

There are three main types of solar eclipses:

1. Total solar eclipse: A total solar eclipse is visible from a small area on Earth. The people who see the total eclipse are in the center of the Moon's shadow when it hits Earth. The sky becomes very dark, as if it were night. For a total eclipse to occur, the Sun, Moon and Earth must be in a direct line.

2. Partial solar eclipse: This happens when the Sun, Moon and Earth are not exactly aligned. The Sun appears to have a dark shadow on a small part of its surface.

3. Annular (an-yə-lər) solar eclipse: An annular eclipse happens when the Moon is farthest from Earth. Because the Moon is farther away, it seems smaller. It does not block the entire view of the Sun. The Moon in front of the Sun looks like a dark disk on top of a larger Sun-colored disk. This creates what looks like a ring around the Moon.

During a solar eclipse, the Moon casts two shadows on Earth.

1. The umbra (əm-brə): This shadow gets smaller as it reaches Earth. It is the dark center of the Moon's shadow. People standing in the umbra will see a total eclipse.

2. The penumbra (pə-ˈnəm-brə): The penumbra gets larger as it reaches Earth. People standing in the penumbra will see a partial eclipse.

Solar eclipses happen every 18 months somewhere on Earth. Unlike lunar eclipses, solar eclipses last only a few minutes.

Never look directly at the Sun: Doing so can permanently damage your eyes! You must use proper safety equipment to look at any type of solar eclipse.

Why Does NASA Study Eclipses?

Hundreds of years ago, when people observed the Moon during an eclipse, they saw Earth's shadow on the Moon and discovered that the Earth is round. Even after all these years, scientists are still learning about the Moon from lunar eclipses. In December 2011, NASA's Lunar Reconnaissance Orbiter gathered data about how quickly the Moon's day side (the side that always faces Earth) cools during a lunar eclipse. NASA can learn what the Moon's surface is made of from this data. If an area of the Moon's surface is flat, it will cool quickly. Scientists use this data to know which areas of the Moon are rough with boulders and which are flat.

Scientists use solar eclipses as an opportunity to study the Sun's corona. The corona is the Sun's top layer. During an annular eclipse, NASA uses ground and space instruments to view the corona when the Moon blocks the Sun's glare.
Remember, never look directly at the Sun: Doing so can permanently damage your eyes!
More about Eclipses
Lunar Eclipses and Solar Eclipses @ NASA Space Place
How Does a Lunar Eclipse Work? Video
What Is an Orbit? Grades 5-8
Read What Is an Eclipse? (Grades K-4)

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An eclipse occurs when one heavenly body such as a moon or planet moves into the shadow of another heavenly body.

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Check out our eclipse maps and animations and find local times for eclipses and planet transits all over the world. We LIVE stream eclipses too!

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The celestial highlight will be the total solar eclipse of April 8, 2024 across North America from Mazatlán to Newfoundland. This eclipse will have a massive impact for several reasons:

31 million people in the US currently live inside the path of totality, with millions more in Canada and Mexico

The path is within 200 miles of many metropolitan areas of the northeastern US and eastern Canada

The duration of maximum totality is 4 minutes and 28 seconds, nearly twice the duration of the 2017 Great American Eclipse which crossed the US

The maximum width of the eclipse path is 122 miles (197.5 km) and includes Mazatlán, Durango, Torreón, San Antonio, Austin, Dallas, Fort Worth, Little Rock, Evansville, Indianapolis, Dayton, Toledo, Cleveland, Buffalo, and Montréal

The dramatic Great American Eclipse of 2017 is still fresh in many people's memories. All who saw it agree it is a peak life experience. We assume that most told family, friends, and neighbors so the anticipation for the 2024 Great American Eclipse will be markedly higher then the lead-up to the 2017 eclipse

The next total solar eclipse of April 8, 2024 in North America begins near Matazlan in Mexico, crosses Texas and the US midwest and northeastern states, and after sweeping above eastern provinces of Canada, ends at sunset in the Atlantic Ocean. The maximum duration of totality will be 4 minutes and 27 seconds near Torreon, Mexico. This duration is nearly double the duration of the 2017 Great American Eclipse across the US.
The times used in the countdown clocks are based on the first external contact of the penumbra. That is, when the Moon's outer shadow first touches the Earth. These time values are from the essential website eclipsewise.com by Fred Espenak.
These are the solar eclipse tracks for this decade. The yellow paths are total solar eclipses and the orange paths are annular solar eclipses. After the 2024 total solar eclipse, these are the total solar eclipses for the remainder of the decade:

August 12, 2026 over Greenland, Iceland, and Spain

August 2, 2027 over northern Africa, Gibraltar, and the Saudi peninsula

July 22, 2028 over Australia and New Zealand

November 25, 2030 over southern Africa and Australia

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When is the next eclipse? - Great American Eclipse

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When is the next eclipse? Future solar eclipses

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Video from Slooh.com is sped up to quickly show the total solar eclipse that occurred over northeastern Australia.

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Honeywell's Space Team delivers unparalleled expertise in space qualified components, systems and mission solutions. We enable seamless satellite connectivity and navigation, empower human space exploration, help create powerful launch vehicles and the smallest microelectronics.

See all of our Satellite Products and Systems HERE.
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Fun Activities To Do @ Home. Launch rockets, build a Moon Habitat, solve spacey puzzles and more! These science, technology, engineering and math activities are fun for kids, adults and the whole family.

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Season simulator | Earth's rotation and tilt | Earth geological and climatic history | Cosmology and astronomy | Science | Khan Academy

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Learn for free about math, art, computer programming, economics, physics, chemistry, biology, medicine, finance, history, and more. Khan Academy is a nonprofit with the mission of providing a free, world-class education for anyone, anywhere.

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There are only two times of the year when the Earth's axis is tilted neither toward nor away from the sun, resulting in a "nearly" equal amount of daylight and darkness at all latitudes. These events are referred to as Equinoxes. The word equinox is derived from two Latin words - aequus (equal) and nox (night). At the equator, the sun is directly overhead at noon on these two equinoxes. The "nearly" equal hours of day and night are due to refraction of sunlight or a bending of the light's rays that causes the sun to appear above the horizon when the actual position of the sun is below the horizon. Additionally, the days become a little longer at the higher latitudes (those at a distance from the equator) because it takes the sun longer to rise and set. Therefore, on the equinox and for several days before and after the equinox, the length of day will range from about 12 hours and six and one-half minutes at the equator, to 12 hours and 8 minutes at 30 degrees latitude, to 12 hours and 16 minutes at 60 degrees latitude.

The summer solstice occurs at the moment the earth's tilt toward/from the sun is at a maximum. Therefore, on the day of the summer solstice, the sun appears at its highest elevation with a noontime position that changes very little for several days before and after the summer solstice. The summer solstice occurs when the sun is directly over the Tropic of Cancer, which is located at 23.5° latitude North and runs through Mexico, the Bahamas, Egypt, Saudi Arabia, India, and southern China. For every place north of the Tropic of Cancer, the sun is at its highest point in the sky and this is the longest day of the year.

The winter solstice marks the shortest day and longest night of the year. In the Northern Hemisphere, it occurs when the sun is directly over the Tropic of Capricorn, which is located at 23.5° south of the equator and runs through Australia, Chile, southern Brazil, and northern South Africa.

For a complete listing of the dates of the winter and summer solstices and spring and fall equinoxes through 2025, check out this site from the U.S. Naval Observatory. An alternative text link is found here.

We all know that the Earth makes a complete revolution around the sun once every 365 days, following an orbit that is elliptical in shape. This means that the distance between the Earth and Sun, which is 93 million miles on average, varies throughout the year. During the first week in January, the Earth is about 1.6 million miles closer to the sun. This is referred to as the perihelion. The aphelion, or the point at which the Earth is about 1.6 million miles farther away from the sun, occurs during the first week of July. This fact may sound counter to what we know about seasons in the Northern Hemisphere, but actually, the difference is not significant in terms of climate and is NOT the reason why we have seasons. Seasons are caused by the fact that the Earth is tilted on its axis by 23.5°. The tilt's orientation with respect to space does not change during the year; thus, the Northern Hemisphere is tilted toward the sun in June and away from the sun in December, as illustrated in the graphic below.

There is a lag between the longest day of the year and the warmest average temperatures for most mid and high-latitude locations.

In northern OH/Northwest PA, the maximum daily temperature occurs nearly 3 weeks later in mid-July. Just as the warmest part of the day usually occurs several hours following noon, when the sun is highest in the sky, so too does the warmest part of the summer lags the summer solstice. This lag is due to the time required for ground and water to heat up. Average temperatures continue to climb until the sun drops lower in the sky. While the effect is evident in a daily temperature plot, it is more readily apparent by looking at changes in the monthly average temperature. In Cleveland, July averages 3.3°F degrees higher than June, with August also warmer than June by 2.8°F, even though the length of days in August is considerably less than the length of days in June.

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The Seasons, the Equinox, and the Solstices

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There are only two times of the year when the Earth's axis is tilted neither toward nor away from the sun, resulting in a "nearly" equal amount of daylight and darkness at all latitudes. These events are referred to as Equinoxes. The word equinox is derived from two Latin words - aequus (equal) and nox (night).

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A solstice is an event in which a planet's poles are most extremely inclined toward or away from the star it orbits.

On our planet, solstices are defined by solar declination-the latitude of Earth where the sun is directly overhead at noon. On Earth, solstices are twice-yearly phenomena in which solar declination reaches the Tropic of Cancer in the north and the Tropic of Capricorn in the south. During the June solstice (marked between June 20 and June 22), solar declination is about 23.5°N (the Tropic of Cancer). During the December solstice (marked between December 20 and December 23), solar declination is about 23.5°S (the Tropic of Capricorn).

Solstices and shifting solar declinations are a result of Earth's 23.5° axial tilt as it orbits the sun. Throughout the year, this means that either the Northern or Southern Hemisphere is tilted toward the sun and receives the maximum intensity of the sun's rays. (The only times of the year when the intensity of the sun's rays is not unequal are the appropriately named equinoxes. During an equinox, solar declination is 0°-the Equator-and both the Northern and Southern Hemisphere receive equal sunlight.)

Sometimes, solstices are nicknamed the "summer solstice" and the "winter solstice," although these have different dates in the Northern and Southern Hemispheres. The summer solstice is the longest day of the year, meaning it experiences the maximum intensity of the sun's rays and has the most hours of sunlight. The winter solstice is the shortest day of the year and has the fewest hours of daylight.

The June solstice is the summer solstice in the Northern Hemisphere and the winter solstice in the Southern Hemisphere. The December solstice is the winter solstice in the Northern Hemisphere and the summer solstice in the Southern.﻿

Earth's latitudes experience the solstices in different ways. At the poles, a solstice is the peak of a radical exposure to daylight, while at the Equator, the solstices are barely marked at all.
Equatorial Regions
The Equator, at 0° latitude, receives a maximum intensity of the sun's rays all year.

As a result, areas near Earth's Equator experience relatively constant sunlight and little solstice variation.
Midlatitudes
Earth's solstices are largely marked by the transition of the subsolar point across the tropics.

The subsolar point describes the latitude where the sun's rays hit Earth exactly perpendicular to Earth's surface. It is where the sun appears directly overhead at noon. The subsolar point appears at the Equator twice a year (during the equinoxes), and migrates north and south across the tropics during the rest of the year. The solstices mark when the subsolar point reaches its northernmost and southernmost latitudes.

The sun's vertical rays strike the Tropic of Cancer, 23.5° north of the Equator, during the June solstice. The subsolar point then begins its migration south, and vertical rays strike the Tropic of Capricorn, 23.5° south of the Equator, during the December solstice. The subsolar point will cross every latitude between these extremes twice every year.
Polar Regions
The subsolar point never reaches Arctic and Antarctic regions. At the North Pole and South Pole, the solstices mark the time when the sun is highest or lowest in the sky. In this way, solstices are the extreme examples of "midnight sun" and "polar night."

"Midnight sun" describes the phenomenon surrounding the summer solstice, when the sun remains visible at midnight in the weeks leading up to and following the event. The "polar night" surrounds the winter solstice, when the sun remains below the horizon during the weeks leading up to and following the event.
Extraterrestrial Solstices
Every planet in our solar system experiences solstices. The timing and extent of solstices are largely determined by the planet's axial tilt, orbital eccentricity, and distance from the sun.

Venus, the planet closest to Earth, has a very small axial tilt, just 3°. Venus experiences very little seasonal variation, and its solstices are separated by about three months.

Mars, our other close neighbor, has an axial tilt similar to Earth (24°). However, Mars has a significantly greater orbital eccentricity, meaning it orbits the sun in a more elliptical shape than Earth. As a result of Mars' larger orbital eccentricity and axial tilt, the Red Planet experiences extreme seasonal variations and its solstices are about 11 months apart.

The Culture of the Solstices

Solstices now mark the beginning of winter and summer, but because some ancient cultures only recognized these two seasons (there was no autumn or spring), the solstices occurred in the middle of the season. Solstices are known as midwinter and midsummer for this reason.

Since ancient times, many cultures have marked the solstices with holidays and festivals.

Followers of many ancient traditions honored the winter solstice, which signaled the cold, winter season. Winter weather put ancient cultures at their most vulnerable; both food and shelter were limited. Many festivities emphasize light, recognizing the winter solstice as the shortest, darkest day of the year.

In many cultures, holidays surrounding midwinter are more prayerful than celebratory-they include cultures praying for survival through the dark and cold, as well as celebrating the spirit of cooperation that helps communities survive difficult times. In other places, midwinter celebrations are the last festivals before the long "famine months" of winter.

Monuments to midwinter holidays can be seen at Stonehenge, in Great Britain, and the so-called Intihuatana Stone (the so-called "hitching post of the sun") at the Incan ruin of Machu Picchu in Peru. At these sites, people gathered to celebrate and pray for their survival through the rest of winter.

In Japan, midwinter (toji﻿) is marked by traditional yuzuyu hot citrus baths. Yuzuyu are practical as well as symbolic. The hot tubs filled with dozens of citrus fruit are intended to focus prayers for the new year, as well as warm the body and soothe skin chapped by winter winds.

The Sha'lak'o midwinter dance is a custom among the Zuni peoples of what is now the Southwestern United States. During the Sha'lak'o, dancers representing the Zuni fire god and rain god, help the communities bid farewell to the old year and seek blessings in the new.

Perhaps the most famous midwinter celebration is the Saturnalia of Ancient Rome. Saturnalia was celebrated the weeks leading up to the actual solstice. Saturnalia was a wild carnival, as well as a time to mark the passing of the seasons. During Saturnalia festivities, Romans enjoyed banquets, gambling, jokes, gifts, and a tradition of usurping strict social structures. At Saturnalia feasts, masters may have served their slaves, and a "King of Saturnalia" could be appointed to manage merrymaking-decreeing that guests must jump in a river or wear outrageous costumes, for instance.

Early Christians adopted the timing of Saturnalia for two of their most important seasons, Advent and Christmas. Pagans and neopagans, followers of early European religious traditions, still celebrate the winter solstice as a holiday called Yule.

Midsummer heralded the height of agricultural fertility and the slow onset of the harvest season. The growing and harvesting of crops, management of domestic animals, and the ability to hunt wild game were all crucial to the survival of ancient cultures. Midsummer festivals are often celebrations of nature's bounty.

Ancient European tribes celebrated midsummer with feasts and bonfires, intended to drive away evil spirits. In Alpine and Germanic regions, summer solstice bonfires are so ingrained in the cultures they have their own name: Sonnwendfeuer. Many of these traditions still survive in Europe and countries that have large populations with European (especially Scandinavian) heritage, such as Canada and the United States.

In Finland, midsummer (Juhannus) celebrations include bonfires, saunas, and barbeques. Due to Finland's proximity to the Arctic, the summer solstice itself can have very little darkness. This makes midsummer in Scandinavia an ideal time for weeklong outdoor music festivals and family vacations.

In Ancient Egypt, the summer solstice signaled the beginning of the new year. Sirius, the brightest star in the night sky, appeared soon after the summer solstice. Egyptian astronomers associated the annual appearance of Sirius with the seasonal flooding of the Nile River, which the civilization depended on for agriculture.

Due to its association with fertility and abundance, midsummer is often associated with romance and marriage. One of the most famous expressions of this romantic sentiment is the comic play "A Midsummer Night's Dream," by the English writer William Shakespeare. In the play, fairies enchant two couples in a magical forest-and haphazardly get enchanted themselves. The play's many role-reversals and changes in appearance are thematically tied to the solstice.

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A solstice is an event in which a planet's poles are most extremely inclined toward or away from the star it orbits.

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An equinox is an event in which a planet's subsolar point passes through its Equator. The equinoxes are the only time when both the Northern and Southern Hemispheres experience roughly equal amounts of daytime and nighttime.

On Earth, there are two equinoxes every year: one around March 21 and another around September 22. Sometimes, the equinoxes are nicknamed the "vernal equinox" (spring equinox) and the "autumnal equinox" (fall equinox), although these have different dates in the Northern and Southern Hemispheres.

The March equinox is the vernal equinox in the Northern Hemisphere, and the autumnal equinox in the Southern. The September equinox is the autumnal equinox in the Northern Hemisphere and the vernal in the Southern.

The Science of the Equinoxes

During the equinoxes, solar declination is 0°. Solar declination describes the latitude of Earth where the sun is directly overhead at noon. (The Equator, of course, is 0° latitude.) So, equinoxes are the only times of the year when the subsolar point is directly on the Equator.

The subsolar point is an area where the sun's rays shine perpendicular to Earth's surface-a right angle. Only during an equinox is Earth's 23.5° axis not tilting toward or away from the sun: the perceived center of the Sun's disk is in the same plane as the Equator.

Before and after the equinox, the subsolar point migrates north or south. After the March equinox, the subsolar point migrates north as the Northern Hemisphere tilts toward the sun. Around June 21, the subsolar point hits the Tropic of Cancer, (23.5°N). This is the June solstice, after which the subsolar point begins to migrate south. After the September equinox, the subsolar point continues to move south as the Southern Hemisphere tilts toward the sun. Around December 21, the subsolar point hits the Tropic of Capricorn (23.5°S). This is the December solstice.

As its name suggests, an equinox indicates equally illuminated hemispheres, with the solar terminator equally dividing Earth from north to south. (The solar terminator is the shadowed line indicating daylight and sunlight on a globe.) A true equinox would indicate 12 hours of both day and night.

Although the equinoxes are as close to this phenomenon as happens on Earth, even during the equinoxes day and night aren't exactly equal. This is largely due to atmospheric refraction. Atmospheric refraction describes the way light seems to bend or deviate from a straight line as it passes through Earth's atmosphere. Atmospheric refraction is a result of increasing air density, which decreases the velocity of light through the air. Due to atmospheric refraction, we are able to see the sun minutes before it actually rises and sets.
Equatorial Regions
The Equator, at 0° latitude, receives a maximum intensity of the sun's rays all year. As a result, areas near Earth's Equator experience relatively constant sunlight and little equinoctial variation. Equinoxes and celestial seasons generally have less impact than climate-driven patterns such as precipitation (rainy seasons and dry seasons).
Midlatitudes
Seasonal variation increases with latitude. Atmospheric refraction also increases the disparity in the "equinox" length of day and night. At about 30° latitude, day is about eight minutes longer than night.
Polar Regions
Atmospheric refraction is most dramatic in the Arctic and Antarctic, with daylight extending about 12 hours and 16 minutes. In this way, the equinoxes in polar regions signal the slow change from "midnight sun" to "polar night." "Midnight sun" describes the phenomenon in which the sun never dips below the horizon, keeping the region bathed in sunlight 24 hours a day. "Polar night" describes the opposite phenomenon, a time in which the sun never rises, keeping the region dark for 24-hour periods.
Equinoctial Disruptions
Satellites are vulnerable to disruptions in the days before and after an equinox. "Sun outages" describe this disruption. In the Northern Hemisphere, sun outages occur in the days before the March equinox and after the September equinox. In the Southern Hemisphere, sun outages occur after the March equinox and before the September equinox.

During an equinox, the sun is aligned directly behind satellites in geostationary orbit at the Equator. Situated directly above the subsolar point, the satellites are flooded with direct solar radiation. This solar radiation can interfere with and even stop satellites from transmitting signals. Many communications satellites orbit around the Equator, and consumers may experience slow Internet connections, radio static, or frozen television screens during equinoctial sun outages.
Extraterrestrial Equinoxes
Most planets experience equinoxes. The timing of equinoxes is determined by the planet's axial tilt and orbital characteristics. On the gas giant Saturn, for example, equinoxes are particularly dramatic. About 15 years separate the equinoxes on Saturn, and the equinoxes last about four days.

Saturn's spectacular ring system orbits in the same plane as the planet's equator. Although the rings extend thousands of kilometers into space, they are actually very thin, only about a kilometer wide. During Saturn's equinoxes, the rings (and Saturn's equator) line up perfectly with the sun. Photos taken from the solar perspective reveal the rings as a razor-thin line.
The Culture of the Equinoxes
Like the solstices, equinoxes are historic markers of seasonal change.
March Equinox
The March equinox, unofficially marking the spring season, is traditionally observed as a time of rebirth and renewal. For this reason, many cultures have celebrated the March equinox as the first day of the new year. The ancient Babylonian calendar began on the first full moon after the March equinox, and today, many cultural and religious calendars continue to celebrate new year in the spring.

Perhaps the most widespread and well-known equinoctial new year is Nowruz, the first day of the year in the Persian calendar. For more than 3,000 years, Nowruz has been a religious holiday in Zoroastrianism, but today it is marked by secular celebrations throughout Eastern Europe and Central Asia. The Nowruz holiday includes mythical figures (such as Amu Nowruz, sometimes nicknamed the "Iranian Santa Claus"), traditional family gatherings, and the items of "haft-sin."

Haft-sin are seven symbolic foods associated with Nowruz, all beginning with the Arabic or Persian letter sin: sabze (sprouts, symbolizing rebirth); samanu (sweet pudding, symbolizing wealth); senjed (dried, date-like fruits, symbolizing love); seer (garlic, symbolizing health); seeb (apples, symbolizing beauty); somac (red sumac fruit, symbolizing the color of sunrise); and serkeh (vinegar, symbolizing age and wisdom).

Outside new year celebrations, the March equinox is celebrated in holidays all over the world. Vernal Equinox Day is a national holiday in Japan. The Jewish festival of Passover begins the night of a full moon after the March equinox. The date of Easter, one of the most important holidays in the Christian calendar, is calculated using the March equinox.
September Equinox
Fewer events mark the September equinox. Perhaps the most familiar of these are Rosh Hashanah and Yom Kippur, Judaism's "High Holy Days." Rosh Hashanah is the Jewish new year, marked around the September equinox. Rosh Hashanah is calculated as 163 days after the first day of Passover (which itself is calculated by the March equinox.) The sounding of the shofar, a ram's horn used as a trumpet for thousands of years of Jewish ritual, welcomes Rosh Hashanah.

Yom Kippur, the holiest day in the Jewish calendar, falls about 10 days after Rosh Hashanah. Yom Kippur is a solemn holiday known as the "Day of Atonement." It is traditionally observed with a daylong fast and prayers for forgiveness.

Most cultural events associated with the September equinox are tied to autumnal harvest festivals. Chuseok, celebrated over a three-day period in the Koreas, is one of the most familiar of these folk festivals. Sometimes nicknamed "Korean Thanksgiving," Chuseok is a celebration of family and Korea's rich agricultural heritage.

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An equinox is an event in which a planet's subsolar point passes through its Equator.

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A season is a period of the year that is distinguished by special climate conditions

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Seasons Interactive

Each year on Earth, we observe patterns of changing temperatures, daylight hours, and seasons. In this activity, you will use a computer simulation to model Earth's orbit around the Sun to help understand why we observe these patterns.

Resources

Student Book Pages and Student Sheets

Interactive

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Each year on Earth, we observe patterns of changing temperatures, daylight hours, and seasons. In this activity, you will use a computer simulation to model Earth's orbit around the Sun to help understand why we observe these patterns. Student Book Pages and Student Sheets

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Taken from the November 2019 issue of Physics World. Members of the Institute of Physics can enjoy the full issue via the Physics World app.

As the name suggests, science-fiction movies are just that - fiction. Unfortunately, that sometimes means the science is too. Rhett Allain examines some concepts that sci-fi movies regularly get wrong

Whether they're about space travel, superheroes, aliens, sentient robots or all the above and beyond, science-fiction movies are more popular than ever. Indeed, six out of the top 10 grossing films of 2018 were part of the sci-fi genre, including Avengers: Infinity War, Ant-Man and the Wasp, and Solo: a Star Wars Story.

But let's be clear - even though these movies involve some element of science, they are still fiction, and their sole purpose is to entertain. So despite the best efforts of science advisers (see " Turning science into movie magic "), the science in the films is sometimes questionable. You'll have your own favourite examples of "bad movie science", but let's look at three concepts that regularly put the fiction into science fiction.

Airlocks and gravity

Imagine the following scene (or remember WALL-E (2008) or Sunshine (2007) if you prefer). An astronaut is floating in space. Far from a planet or star, our hero pries open the airlock of a spacecraft before going inside. The outer door shuts, and the isolated chamber fills with air. Then, as if by magic, the astronaut suddenly falls to the ship's floor seemingly under the influence of gravity.

Unless the ship has some futuristic gravity-inducing technology - like in the Star Trek (1966-present) and Star Wars (1977-present) franchises - the implication in these scenes is that because space has neither gravity nor air, the presence of air in the spacecraft means gravity kicks in.

Nope. That's not how it works.

Gravity is an interaction between any two objects with mass, and it is so weak that you would never notice the force between any two normal sized objects. However, if one of the interacting masses is huge - and sci-fi movies just love massive asteroids, planets and black holes - then the gravitational force is noticeable. That means that there is indeed gravity in space, depending on where you are in relation to big objects. It's why the Earth moves around the Sun even though there is no air out there.

So, for our astronaut in deep space, even after the airlock chamber is up to pressure, they should still be floating around.

It's a bit different if the spaceship is in low orbit around a huge object - like the International Space Station (ISS) circling the Earth. Astronauts on the ISS only appear to be without gravity because of the orbital motion of the space station. The ISS is accelerating as it moves in a circular path around the Earth, but since the humans inside are experiencing the same acceleration as the ISS (due to the gravitational interaction), they "feel" weightless. The same thing can happen on the surface of the Earth - there are many popular amusement-park rides that place you in a free-falling seat. For the short moment that both the ride and the humans have the same free-fall acceleration, the humans will be "weightless".

There's an obvious reason why moviemakers use the misconception that the presence of air in a spaceship means gravity - it's much easier to film. On Earth, creating weightless scenes is hard. One option is to send your star actors (or doubles) onto a plane and get the pilots to perform a parabolic manoeuvre, which is how scenes in the 1995 movie Apollo 13 were filmed. Other tactics are to move actors around with complex string systems that get edited out, or to film underwater - both of which were put into effect for Gravity (2013). You could also use computer animations to simulate weightlessness. But given the complexities of each of these methods, it's easier for movie directors to have the actors move around with gravity instead of bothering with those fancy special-effect tricks. So, when the air gets pumped back into an airlock, this makes an easy transition point for movie-makers to have characters go from "floating around" in space to being in a space ship.

One movie that gets the science right with airlocks is 2001: A Space Odyssey (1968) (see " Douglas Trumbull: a mutual appreciation between scientists and moviemakers", Nov 2019). The lead character, a scientist called David Bowman, is in a small spacepod and he needs to get back into the large spacecraft Discovery One. Unfortunately, he's left his spacesuit helmet behind during his travels and the computer (HAL) doesn't want to let him back in. In a daring move, Bowman opens the spacepod door and shoots himself into an empty airlock - in which he (correctly) bounces around even as you can hear the air hissing back in.

Movies like Interstellar (2014) and The Martian (2015) go down the artificial-gravity route for their spaceships, but induce it in a scientifically realistic way, rather than using some mysterious futuristic technology off-screen. In these films, the astronauts experience a normal Earth-like gravity due to the rotation of the spaceship. By standing on the inside of a rotating object, the floor will have to push on the humans in order to make them move in a circle. If this force from the rotating floor has the same magnitude as the force the ground on Earth pushes back with, an astronaut would feel the effects of artificial gravity. This isn't science fiction, but actual science.

Spacecraft and thrusters

As well as featuring airlocks, just about every science-fiction movie that takes place in space will have an obligatory scene where a big and ominous spaceship is seen travelling steadily through the void with a deep rumble. The noise is the first error as sound obviously can't travel in a vacuum. But as the spaceship passes the "camera", it gets worse. Viewers glimpse massive engines glowing from the use of thrusters that are apparently pushing the ship forward. Newton's second law of motion says no. Forces don't make things move - forces make things change speed.

On Earth, if you wanted to push an object across a table, say, at constant speed, you'd obviously need to apply a constant force to overcome the friction between the surface and the object, and the air resistance. When travelling through the vacuum of space, however, these opposing forces are not present. You only need to apply an initial force to accelerate into motion, change direction, speed up or slow down. For a starship travelling at a constant speed, it wouldn't need the thrusters on at all.

So why do so many movies get this simple fact wrong? The fault lies with our everyday experience of moving objects over surfaces, which wrongly implies that you need a constant force to move them at a constant speed. It's only when you consider the invisible frictional force that you realize why that's not true.

Of course, not every sci-fi show gets this fact wrong. My favourite example is not a movie but the Syfy and Prime Video TV series The Expanse (2015 - present). This show takes place mostly in our own solar system using spacecraft that are pretty plausible. The vehicles move around using thrusters - but they don't travel at a constant speed. Instead, the thrusters make the spacecraft accelerate and speed up. Then, when the starship is halfway to its destination, it flips around and uses the thrusters to slow down.

The show also uses these thrusters for artificial gravity. Since the spacecraft is accelerating, the people inside also need to accelerate. And in order for a human to accelerate, that human would need a net force. This net pushing force comes from the floor in the interior of the ship. It can be very similar to the force of the ground pushing on you now (assuming you are on Earth) such that it feels like gravity.

The biggest downside to using more plausible physics when portraying space travel is that the ships might then move in a way that will strike viewers as odd, unrealistic and unexpected. Not having ever travelled in space, most of us simply don't have an intuition for how things would behave out there.

Massive and moving

Sci-fi films aren't just set in space - sometimes a plot will unfold right here on the surface of the Earth. But still, it needs to be exciting and different in some way, and what better way to do that than to throw in huge robots, machines or monsters.

Take the Pacific Rim movies ( 2013 and 2018), which feature gigantic humanoid machines known as Jaegers, controlled by two or three co-pilots. Deployed to battle Godzilla-like monsters from an interdimensional portal, these machines are about 75-100 m tall. The question is, though, how would something this big move?

Well, imagine throwing a tennis ball vertically upwards to a certain height, h. Simple Newtonian mechanics says that the time for the ball to fall back down into your hand is t = 2(2 h/ g) 1/2, where g is the acceleration due to gravity. So if you throw a ball up a metre, it takes about a second for the ball to go up and back down.

Now imagine a giant 100 m Jaeger fighting a huge monster. If, in the course of the struggle, the robot takes a huge 20 m jump (just 20% the height of the robot) then, using the formula above, it'll be off the ground for four seconds. That might not seem much, but in the world of films, it's enough to turn a fast-paced action scene into a slow-motion ballet. To keep the movie magic, filmmakers tend to bend the laws of physics and speed up the robot's movements - they make these giant humanoids move like normal humans, only bigger.

The same idea also works for things like punching. A human-sized arm can accelerate and move to a fully extended position in just a fraction of a second. So if you want a robot with an arm that is much larger to do the same motion in the same time, both the acceleration and velocity would have to be much higher.

Let's say you have a human arm making a punching motion. As a rough estimate, this fist starts from rest and then moves a distance of about 50 cm (the length of an outstretched arm), and the whole punching motion takes under 0.1 s to complete. During this time, the fist accelerates up to speed and then slows down to stop. If the punching hand has a constant acceleration during the first half of the punch, basic kinematics says it would get up to a top speed of 5 m/s.

Now if you repeat this same calculation for a punch made by a giant 100 m-high robot, then - assuming it has the same proportions as a normal human - its punch will extend over a distance of about 25 m. But in order for the punching robot to look like a fighting human, it would still need to complete the punch in a time of about 0.1 s. Using the same time with the larger distance gives a maximum punching speed of 250 m/s. Just for comparison, this robot punching speed is about the speed of a flying commercial airliner. Yes, super fast.

The physics also gets complicated when things get tiny. In the movie Ant-Man (2015) the hero, played by Paul Rudd, has the power to shrink down to less than 1 cm in height, which would make even running extremely hard. For each stride of his run, he would be off the ground for a very short period of time. Sure, he could run - but it certainly wouldn't look like a normal human running.

Turning science to movie magic

You might think that none of the physics I've described in this article is particularly cutting-edge or advanced - and that by picking holes in movie plot lines I'm spoiling the drama of Hollywood blockbusters. To some extent, you'd be right. However, examining the scientific principles in sci-fi movies is a great way of getting school students and non-scientists interested in simple science. There are countless examples that you can use and there's always a new movie around the corner. So next time you're rolling your eyeballs at a film that mangles the science, go home, do a few back-of-the-envelope calculations and you've got a perfect talking point to reveal to others the beauty and wonder of science.

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The fictional science of science fiction - Physics World

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Rhett Allain explores three common scientific mistakes seen regularly in science-fiction movies

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Science and the Impossible: Influence of Science-fiction on Science

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All stars form in nebulae, which are huge clouds of gas and dust. Though they shine for many thousands, and even millions of years, stars do not last forever. The changes that occur in a star over time and the final stage of its life depend on a star's size.

Life Cycle of a Star
Credit:NASA

Nuclear reactions at the centre (or core) of a star provides energy which makes it shine brightly. This stage is called the ' main sequence'. The exact lifetime of a star depends very much on its size. Very massive stars use up their fuel quickly. This means they may only last a few hundred thousand years. Smaller stars use up fuel more slowly so will shine for several billion years.

Eventually, the hydrogen which powers the nuclear reactions inside a star begins to run out. The star then enters the final phases of its lifetime. All stars will expand, cool and change colour to become a red giant. What happens next depends on how massive the star is.

A smaller star, like the Sun, will gradually cool down and stop glowing. During these changes it will go through the planetary nebula phase, and white dwarf phase. After many thousands of millions of years it will stop glowing and become a black dwarf.

A massive star experiences a much more energetic and violent end. It explodes as a supernova. This scatters materials from inside the star across space. This material can collect in nebulae and form the next generation of stars. After the dust clears, a very dense neutron star is left behind. These spin rapidly and can give off streams of radiation, known as pulsars.

If the star is especially massive, when it explodes it forms a black hole.

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All stars form in nebulae, which are huge clouds of gas and dust. Though they shine for many thousands, and even millions of years, stars do not last forever. The changes that occur in a star over time and the final stage of its life depend on a star's size.

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The Sun | Crash Course Astronomy | PBS LearningMedia

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Phil takes us for a closer look at the two-octillion-ton star that rules our solar system. We look at the sun's core, plasma, magnetic fields, sunspots, solar flares, coronal mass ejections, and what all of that means for our planet.

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Space Weather describes the variations in the space environment between the sun and Earth. In particular Space Weather describes the phenomena that impact systems and technologies in orbit and on Earth. Space weather can occur anywhere from the surface of the sun to the surface of Earth.

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Despite its apparently steady glow, the Sun is a churning mass of superhot plasma that regularly produces powerful flares and storms that can knock out power and communication systems on Earth. This Lab explores what makes the Sun so volatile and gives you access to the same data, images, and tools that scientists use to predict solar storms.

Challenge Video Intro About this Lab Educator Guide

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sun lab research data solar space weather storm flare corona cme satellite sdo sunspot

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Investigate solar storms using live images from NASA telescopes.

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This simulator models the motions of the sun in the sky using a horizon diagram, demonstrating daily and seasonal changes in the sun's position.

The upper left panel shows the horizon diagram visualization. This is a representation of the sky as if it were a large sphere centered on an observer (the stickfigure). The location and local time for this observer are set in the Time and Location Controls panel.

The General Settings panel allows one to show or hide various features of the horizon diagram, as well as controlling the behavior when dragging the sun disk on the horizon diagram.

When animating, this simulator can run continuously (as if in fast forward) or it can step by day. Stepping by day keeps the time of day fixed as the day of year changes. For example, one can use this mode to see the path the noon time sun traces over the year.

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This simulator models the motions of the sun in the sky using a horizon diagram, demonstrating daily and seasonal changes in the sun's position. The upper left panel shows the horizon diagram visualization. This is a representation of the sky as if it were a large sphere centered on an observer (the stickfigure).