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the history of exploring saturn: NASA´s pioneer 11 was the 1st spacecraft to visit saturn, getting within 20,000km of the planet´s cloud layers. It was followed by voyager 1 in 1980, and voyager 2 in august 1981. It wasn´t until july 2004 that NASA´s Cassini spacecraft arrived at saturn, and began the most detailed exploration of the system.

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the history of exploring saturn: NASA´s pioneer 11 was the 1st spacecraft to visit saturn, getting within 20,000km of the planet´s cloud layers. It was followed by voyager 1 in 1980, and voyager 2 in august 1981. It wasn´t until july 2004 that NASA´s Cassini spacecraft arrived at saturn, and began the most detailed exploration of the system.

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Saturn is easily visible with the unaided eye, so it's hard to say when the planet was first discovered. The Romans named the planet after Saturnus, the god of the harvest - it's the same as the Greek god Kronos.

You can also check out these cool telescopes that will help you see the beauty of planet Saturn.

Nobody realized the planet had rings until Galileo first turned his rudimentary telescope on the planet in 1610. Of course, Galileo didn't realize what he was looking at, and thought the rings were large moons on either side of the planet.

It wasn't until Christian Huygens used a better telescope to see that they were actually rings. Huygens was also the first to discover Saturn's largest moon Titan.

Jean-Domanique Cassini uncovered the gap in Saturn's rings, later named the Cassini Division, and he was the first to see 4 more of Saturn's moons: Iapetus, Rhea, Tethys, and Dione.

There weren't many more major discoveries about Saturn until the spacecraft flybys in the 70s and 80s. NASA's Pioneer 11 was the first spacecraft to visit Saturn, getting within 20,000 km of the planet's cloud layers. It was followed by Voyager 1 in 1980, and Voyager 2 in August 1981.

It wasn't until July 2004 that NASA's Cassini spacecraft arrived at Saturn, and began the most detailed exploration of the system. Cassini has performed multiple flybys of many of Saturn's moons, and sent back thousands of images of the planet and its moons. It has discovered 4 new moons, a new ring, and saw liquid hydrocarbon seas on Titan.

This article was published when Cassini had finished half its primary mission, and discusses many of the discoveries made so far, and another article when its primary mission was complete.

This article has a timeline of Saturn history, and more history from NASA.

We have recorded two episodes of Astronomy Cast just about Saturn. The first is Episode 59: Saturn, and the second is Episode 61: Saturn's Moons.

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Saturn is easily visible with the unaided eye, so it's hard to say when the planet was first discovered. The Romans named the planet after Saturnus, the god of the harvest - it's the same as the Greek god Kronos. You can also check out these cool telescopes that will help you see the beauty ...

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saturn has 82 moons but has 15 major moons

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saturn has 82 moons but has 15 major moons

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saturns rings are made of ice and rock, and look like race tracks

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saturns rings are made of ice and rock, and look like race tracks

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In Depth | Saturn – NASA Solar System Exploration

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NASA’s real-time science encyclopedia of deep space exploration. Our scientists and hardworking robots are exploring the wild frontiers of our solar system.

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the temperature of saturn is -220 degrees Fahrenheit (-140 degrees Celsius)

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the temperature of saturn is -220 degrees Fahrenheit (-140 degrees Celsius)

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Source: NASA Planetary Fact Sheet

Published: February 15, 2022

This graphic shows the mean temperatures of various destinations in our solar system. (Planets not to scale.)

In general, the surface temperatures of planets decrease with increasing distance from the Sun. Venus is an exception because its dense atmosphere acts as a greenhouse and heats the surface to above the melting point of lead.

Mercury rotates slowly and has a thin atmosphere, and consequently, the night-side temperature can be more than 1,000 degrees Fahrenheit lower than the day-side temperature. It can be as cold as -290°F (-179°C) on Mercury at night.

Temperatures for the gas and ice giants (Jupiter, Saturn, Uranus, and Neptune) are taken from a level in the atmosphere equal in pressure to sea level on Earth.

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Solar System Temperatures | NASA Solar System Exploration

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Source: NASA Planetary Fact Sheet Published: February 15, 2022 This graphic shows the mean temperatures of various destinations in our solar system. (Planets not to scale.) In general, the surface temperatures of planets decrease with increasing distance from the Sun.

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saturns atmosphere is mainly made up of hydrogen

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saturns atmosphere is mainly made up of hydrogen

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US Department of Commerce, NOAA, National Weather Service

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Weather and other quick facts about Saturn

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It is easy to forget just how large Saturn is, at around 10 times the diameter of Earth. And with a diameter of about 72,400 miles (116,500 kilometers), the planet simply dwarfs its retinue of moons. One of those satellites, Tethys (660 miles or 1,062 kilometers across), is seen here at lower right.

This view looks toward the sunlit side of the rings from about 8 degrees above the ring plane. The image was taken with the Cassini spacecraft wide-angle camera on March 7, 2015 using a spectral filter that preferentially admits wavelengths of near-infrared light centered at 752 nanometers.

Tethys has been brightened by a factor of 2 to increase its visibility.

The view was acquired at a distance of approximately 1.6 million miles (2.6 million kilometers) from Saturn. Image scale is 10 miles (16 kilometers) per pixel. Tethys is slightly closer at 1.5 million miles (2.4 million kilometers) away, for an image scale of 9 miles (14 kilometers) per pixel.

The Cassini mission is a cooperative project of NASA, ESA (the European Space Agency) and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colorado.

For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov or http://www.nasa.gov/cassini . The Cassini imaging team homepage is at http://ciclops.org .

Credit: NASA/JPL-Caltech/Space Science Institute

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Saturn the Mighty | NASA Solar System Exploration

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It is easy to forget just how large Saturn is, at around 10 times the diameter of Earth. And with a diameter of about 72,400 miles (116,500 kilometers), the planet simply dwarfs its retinue of moons. One of those satellites, Tethys (660 miles or 1,062 kilometers across), is seen here at lower right.

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it takes 29.4 earth years for saturn to revolve around the sun

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it takes 29.4 earth years for saturn to revolve around the sun

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In Depth | Saturn – NASA Solar System Exploration

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NASA’s real-time science encyclopedia of deep space exploration. Our scientists and hardworking robots are exploring the wild frontiers of our solar system.

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it takes 10.7 hrs for saturn to rotate on its axis

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it takes 10.7 hrs for saturn to rotate on its axis

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In Depth | Saturn – NASA Solar System Exploration

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NASA’s real-time science encyclopedia of deep space exploration. Our scientists and hardworking robots are exploring the wild frontiers of our solar system.

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the distance from saturn and the sun is 918.47 million mi

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the distance from saturn and the sun is 918.47 million mi

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Saturn is the sixth planet from the Sun and the second-largest planet in our solar system. Like fellow gas giant Jupiter, Saturn is a massive ball made mostly of hydrogen and helium. Saturn is not the only planet to have rings, but none are as spectacular or as complex as Saturn's. Saturn also has dozens of moons.

From the jets of water that spray from Saturn's moon Enceladus to the methane lakes on smoggy Titan, the Saturn system is a rich source of scientific discovery and still holds many mysteries.

Namesake

The farthest planet from Earth discovered by the unaided human eye, Saturn has been known since ancient times. The planet is named for the Roman god of agriculture and wealth, who was also the father of Jupiter.

Potential for Life

Potential for Life

Saturn's environment is not conducive to life as we know it. The temperatures, pressures, and materials that characterize this planet are most likely too extreme and volatile for organisms to adapt to.

While planet Saturn is an unlikely place for living things to take hold, the same is not true of some of its many moons. Satellites like Enceladus and Titan, home to internal oceans, could possibly support life.

Size and Distance

Size and Distance

With a radius of 36,183.7 miles (58,232 kilometers), Saturn is 9 times wider than Earth. If Earth were the size of a nickel, Saturn would be about as big as a volleyball.

From an average distance of 886 million miles (1.4 billion kilometers), Saturn is 9.5 astronomical units away from the Sun. One astronomical unit (abbreviated as AU), is the distance from the Sun to Earth. From this distance, it takes sunlight 80 minutes to travel from the Sun to Saturn.

Orbit and Rotation

Orbit and Rotation

Saturn has the second-shortest day in the solar system. One day on Saturn takes only 10.7 hours (the time it takes for Saturn to rotate or spin around once), and Saturn makes a complete orbit around the Sun (a year in Saturnian time) in about 29.4 Earth years (10,756 Earth days).

Its axis is tilted by 26.73 degrees with respect to its orbit around the Sun, which is similar to Earth's 23.5-degree tilt. This means that, like Earth, Saturn experiences seasons.

Moons

Saturn is home to a vast array of intriguing and unique worlds. From the haze-shrouded surface of Titan to crater-riddled Phoebe, each of Saturn's moons tells another piece of the story surrounding the Saturn system. Currently, Saturn has 53 confirmed moons with 29 additional provisional moons awaiting confirmation.

This Cassini image from 2012 shows Titan and its host planet Saturn. Image Credit: NASA/JPL-Caltech/SSI

Rings

Saturn's rings are thought to be pieces of comets, asteroids, or shattered moons that broke up before they reached the planet, torn apart by Saturn's powerful gravity. They are made of billions of small chunks of ice and rock coated with other materials such as dust. The ring particles mostly range from tiny, dust-sized icy grains to chunks as big as a house. A few particles are as large as mountains. The rings would look mostly white if you looked at them from the cloud tops of Saturn, and interestingly, each ring orbits at a different speed around the planet.

Saturn's ring system extends up to 175,000 miles (282,000 kilometers) from the planet, yet the vertical height is typically about 30 feet (10 meters) in the main rings. Named alphabetically in the order they were discovered, the rings are relatively close to each other, with the exception of a gap measuring 2,920 miles (4,700 kilometers) in width called the Cassini Division that separates Rings A and B. The main rings are A, B, and C. Rings D, E, F, and G are fainter and more recently discovered.

Starting at Saturn and moving outward, there is the D ring, C ring, B ring, Cassini Division, A ring, F ring, G ring, and finally, the E ring. Much farther out, there is the very faint Phoebe ring in the orbit of Saturn's moon Phoebe.

Formation

Saturn took shape when the rest of the solar system formed about 4.5 billion years ago when gravity pulled swirling gas and dust in to become this gas giant. About 4 billion years ago, Saturn settled into its current position in the outer solar system, where it is the sixth planet from the Sun. Like Jupiter, Saturn is mostly made of hydrogen and helium, the same two main components that make up the Sun.

Structure

Like Jupiter, Saturn is made mostly of hydrogen and helium. At Saturn's center is a dense core of metals like iron and nickel surrounded by rocky material and other compounds solidified by intense pressure and heat. It is enveloped by liquid metallic hydrogen inside a layer of liquid hydrogen -similar to Jupiter's core but considerably smaller.

It's hard to imagine, but Saturn is the only planet in our solar system with an average density that is less than water. The giant gas planet could float in a bathtub if such a colossal thing existed.

Surface

As a gas giant, Saturn doesn't have a true surface. The planet is mostly swirling gases and liquids deeper down. While a spacecraft would have nowhere to land on Saturn, it wouldn't be able to fly through unscathed either. The extreme pressures and temperatures deep inside the planet would crush, melt, and vaporize any spacecraft trying to fly into the planet.

Atmosphere

Atmosphere

Saturn is blanketed with clouds that appear as faint stripes, jet streams, and storms. The planet is many different shades of yellow, brown, and gray.

Winds in the upper atmosphere reach 1,600 feet per second (500 meters per second) in the equatorial region. In contrast, the strongest hurricane-force winds on Earth top out at about 360 feet per second (110 meters per second). And the pressure - the same kind you feel when you dive deep underwater - is so powerful it squeezes gas into a liquid.

Saturn's north pole has an interesting atmospheric feature - a six-sided jet stream. This hexagon-shaped pattern was first noticed in images from the Voyager I spacecraft and has been more closely observed by the Cassini spacecraft since. Spanning about 20,000 miles (30,000 kilometers) across, the hexagon is a wavy jet stream of 200-mile-per-hour winds (about 322 kilometers per hour) with a massive, rotating storm at the center. There is no weather feature like it anywhere else in the solar system.

Magnetosphere

Magnetosphere

Saturn's magnetic field is smaller than Jupiter's but still 578 times as powerful as Earth's. Saturn, the rings, and many of the satellites lie totally within Saturn's enormous magnetosphere, the region of space in which the behavior of electrically charged particles is influenced more by Saturn's magnetic field than by the solar wind.

Aurorae occur when charged particles spiral into a planet's atmosphere along magnetic field lines. On Earth, these charged particles come from the solar wind. Cassini showed that at least some of Saturn's aurorae are like Jupiter's and are largely unaffected by the solar wind. Instead, these aurorae are caused by a combination of particles ejected from Saturn's moons and Saturn's magnetic field's rapid rotation rate. But these "non-solar-originating" aurorae are not completely understood yet.

Resources

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In Depth | Saturn - NASA Solar System Exploration

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Saturn is the sixth planet from the Sun and the second-largest planet in our solar system. Like fellow gas giant Jupiter, Saturn is a massive ball made mostly of hydrogen and helium. Saturn is not the only planet to have rings, but none are as spectacular or as complex as Saturn's.

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earth is 950.92 million mi away from saturn

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earth is 950.92 million mi away from saturn

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Saturn, second largest planet of the solar system in mass and size and the sixth nearest planet in distance to the Sun. In the night sky Saturn is easily visible to the unaided eye as a non-twinkling point of light. When viewed through even a small telescope, the planet encircled by its magnificent rings is arguably the most sublime object in the solar system. Saturn is designated by the symbol ♄.

Saturn's name comes from the Roman god of agriculture, who is equated with the Greek deity Cronus, one of the Titans and the father of Zeus (the Roman god Jupiter). As the farthest of the planets known to ancient observers, Saturn also was noted to be the slowest-moving. At a distance from the Sun that is 9.5 times as far as Earth's, Saturn takes approximately 29.5 Earth years to make one solar revolution. The Italian astronomer Galileo in 1610 was the first to observe Saturn with a telescope. Although he saw a strangeness in Saturn's appearance, the low resolution of his instrument did not allow him to discern the true nature of the planet's rings.

Saturn occupies almost 60 percent of Jupiter's volume but has only about one-third of its mass and the lowest mean density-about 70 percent that of water-of any known object in the solar system. Hypothetically, Saturn would float in an ocean large enough to hold it. Both Saturn and Jupiter resemble stars in that their bulk chemical composition is dominated by hydrogen. Also, as is the case for Jupiter, the tremendous pressure in Saturn's deep interior maintains the hydrogen there in a fluid metallic state. Saturn's structure and evolutionary history, however, differ significantly from those of its larger counterpart. Like the other giant, or Jovian, planets-Jupiter, Uranus, and Neptune-Saturn has extensive systems of moons (natural satellites) and rings, which may provide clues to its origin and evolution as well as to those of the solar system. Saturn's moon Titan is distinguished from all other moons in the solar system by the presence of a significant atmosphere, one that is denser than that of any of the terrestrial planets except Venus.

The greatest advances in knowledge of Saturn, as well as of most of the other planets, have come from deep-space probes. Four spacecraft have visited the Saturnian system: Pioneer 11 in 1979, Voyagers 1 and 2 in the two years following, and, after almost a quarter-century, Cassini-Huygens, which arrived in 2004. The first three missions were short-term flybys, but Cassini went into orbit around Saturn for years of investigations, while its Huygens probe parachuted through the atmosphere of Titan and reached its surface, becoming the first spacecraft to land on a moon other than Earth's.

Basic astronomical data

Saturn orbits the Sun at a mean distance of 1,427,000,000 km (887 million miles). Its closest distance to Earth is about 1.2 billion km (746 million miles), and its phase angle-the angle that it makes with the Sun and Earth-never exceeds about 6°. Saturn seen from the vicinity of Earth thus always appears nearly fully illuminated. Only deep space probes can provide sidelit and backlit views.

Like Jupiter and most of the other planets, Saturn has a regular orbit-that is, its motion around the Sun is prograde (in the same direction that the Sun rotates) and has a small eccentricity (noncircularity) and inclination to the ecliptic, the plane of Earth's orbit. Unlike Jupiter, however, Saturn's rotational axis is tilted substantially-by 26.7°-to its orbital plane. The tilt gives Saturn seasons, as on Earth, but each season lasts more than seven years. Another result is that Saturn's rings, which lie in the plane of its equator, are presented to observers on Earth at opening angles ranging from 0° (edge on) to nearly 30°. The view of Saturn's rings cycles over a 30-year period. Earth-based observers can see the rings' sunlit northern side for about 15 years and then, in an analogous view, the sunlit southern side for the next 15 years. In the short intervals when Earth crosses the ring plane, the rings are all but invisible.

Saturn's rotation period was very difficult to determine. Cloud motions in its massive upper atmosphere trace out a variety of periods, which are as short as about 10 hours 10 minutes near the equator and increase with some oscillation to about 30 minutes longer at latitudes higher than 40°. Scientists attempted to determine the rotation period of Saturn's deep interior from that of its magnetic field, which is presumed to be rooted in the planet's metallic-hydrogen outer core. However, direct measurement of the field's rotation was difficult because the field is highly symmetrical around the rotational axis. At the time of the Voyager encounters, radio outbursts from Saturn, apparently related to small irregularities in the magnetic field, showed a period of 10 hours 39.4 minutes; this value was taken to be the magnetic field rotation period. Measurements made 25 years later by the Cassini spacecraft indicated that the field was rotating with a period 6-7 minutes longer. It was believed that the solar wind is responsible for some of the difference between these two measurements of the rotational period. Not until Cassini flew inside Saturn's rings on its final orbits was the rotation period accurately measured. By relating waves observed in the rings to slight variations in Saturn's gravitational field, the rotation period of the planet was determined to be 10 hours 33 minutes 38 seconds. The time differences between the rotation periods of Saturn's clouds and of its interior have been used to estimate wind velocities ( see below The atmosphere).

Because the four giant planets have no solid surface in their outer layers, by convention the values for the radius and gravity of these planets are calculated at the level at which one bar of atmospheric pressure is exerted. By this measure, Saturn's equatorial diameter is 120,536 km (74,898 miles). In comparison, its polar diameter is only 108,728 km (67,560 miles), or 10 percent smaller, which makes Saturn the most oblate (flattened at the poles) of all the planets in the solar system. Its oblate shape is apparent even in a small telescope. Even though Saturn rotates slightly slower than Jupiter, it is more oblate because its rotational acceleration cancels a larger fraction of the planet's gravity at the equator. The equatorial gravity of the planet, 896 cm (29.4 feet) per second per second, is only 74 percent of its polar gravity. Saturn is 95 times as massive as Earth but occupies a volume 766 times greater. Its mean density of 0.69 gram per cubic cm is thus only some 12 percent of Earth's. Saturn's equatorial escape velocity-the velocity needed for an object, which includes individual atoms and molecules, to escape the planet's gravitational attraction at the equator without having to be further accelerated-is nearly 36 km per second (80,000 miles per hour) at the one-bar level, compared with 11.2 km per second (25,000 miles per hour) for Earth. This high value indicates that there has been no significant loss of atmosphere from Saturn since its formation. For additional orbital and physical data, see the table.

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Saturn | Facts, Size, Temperature, Atmosphere, Color, Rings, & Moons

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Saturn, ringed planet that is the second largest planet in the solar system in mass and size and the sixth nearest planet in distance to the Sun. When viewed through even a small telescope, the planet encircled by its magnificent rings is arguably the most sublime object in the solar system.