# data[].attributes.body
 
Because of Proxima Centauri's proximity to Earth, its angular diameter can be measured directly. The star is about one-seventh the actual diameter of the Sun. It has a mass about an eighth of the Sun's mass, and its average density is about 33 times that of the Sun. Although it has a very low average luminosity, Proxima is a flare star that undergoes random dramatic increases in brightness because of magnetic activity. The star's magnetic field is created by convection throughout the stellar body, and the resulting flare activity generates a total X-ray emission similar to that produced by the Sun. The mixing of the fuel at Proxima Centauri's core through convection and its relatively low energy-production rate mean that it will be a main-sequence star for another four trillion years,or nearly 300 times the current age of the universe.

 
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Shauna and Charlotte
Shauna and Charlotte
 The newly discovered planet, known as Proxima b, orbits the star Proxima Centauri, the closest star to the sun. Proxima Centauri is about 4.22 light-years — or 25 trillion miles (40 trillion kilometers) — from Earth.


That's a daunting distance. But an initiative announced this year aims to send superfast miniature probes to Proxima Centauri, on a journey that would take about 20 years. With the discovery of Proxima b, the founders of that initiative are even more eager to get going.

 

In 2015, NASA's New Horizon probe completed its 3-billion-mile (4.8 billion km) journey to Pluto after traveling for about 9.5 years. The spacecraft traveled at speeds topping 52,000 mph (84,000 km/h). At that rate, it would take New Horizons about 54,400 years to reach Proxima Centauri.


Last month, NASAS Juno probe reached speeds of about 165,000 mph (265,000 km/h) as it entered into orbit around Jupiter. At that rate, a probe could reach Proxima Centauri in about 17,157 years. (It should also be noted that there is currently no feasible way to accelerate a craft large enough to carry humans to those speeds.)


In other words, sending a probe to the nearest star system would not be easy.


The founders of the Breakthrough Starshot initiative want to send wafer-thin probes to Proxima Centauri at very high speeds. The plan calls for equipping these probes with thin sails, which would capture the energy imparted by a powerful Earth-based laser.


This laser would accelerate the probes to 20 percent the speed of light (about 134.12 million mph, or 215.85 million km/h), according to the program scientists. At that rate, the probes could reach Proxima Centauri in 20 to 25 years.


But first, scientists and engineers have to build the apparatus that will launch the tiny probes on their journey. In a news conference today (Aug. 24), Pete Worden, chairman of the Breakthrough Prize Foundation, said that a group of experts had convened earlier this week and discussed plans to build a prototype of the Starshot system. However, he added that the full-scale apparatus is at least 20 years off.


"We certainly hope that, within a generation, we can launch these nanoprobes," Worden said. "And so perhaps 20, 25 years from now, we could begin to launch them, and then they would travel for 25 years to get there."


He added that building the full-scale apparatus would likely cost about the same as building the Large Hadron Collider, the largest particle accelerator in the world; that project is estimated to have cost about $10 billion.


"Over the next decade, we will work with experts here at ESO [the European Southern Observatory] and elsewhere to get as much information as possible about the Proxima Centauri planet … even including whether it might bear life, prior to launching mankind's first probe towards the star," Worden said.


Worden said the Breakthrough Prize Foundation also hopes to "obtain similar data about the other nearby stars, Alpha Centauri A and B." (The two Alpha Centauri stars lie about 4.37 light-years from Earth; some astronomers think Proxima Centauri and the Alpha Centauri stars are part of the same system).



Conor Finlay
Conor Finlay
Proxima Centauri is the nearest star, and on August 24, 2016 astronomers announced it likely has a planet. This star is the nearest of a triple star system, which we on Earth see with the eye alone as the single star Alpha Centauri, visible from Earth’s Southern Hemisphere. They are about four light-years away.

The diagram above shows you where Alpha Centauri is, with respect to other nearby stars. It’s like that in the Nearest Stars section of the Astronomical Companion, but from a viewpoint that has moved closer and to a different angle so as to get a better look at Alpha Centauri. Included are stars within 12 light-years from the sun. The glows of light representing the stars are millions of times larger than the stars themselves, which would be microscopically small on this scale.

The grid serves to show the equatorial plane, and also the scale, the lines being 4 light-years apart. The slightly thicker line is the vernal equinox direction (the Earth-sun direction at March 20).


Imaginary stalks from the plane to the stars show how far north or south they are. I’ve cropped the picture so that some of the stars are off the top or bottom, but they are obscure stars you may not have heard of, with designations such as Lalande 21185, Luyten 726-8, DX Cancri. Most stars, including most of those near to us, are smaller than our sun – red dwarfs.

The exceptions near to us are Sirius, Procyon, and Alpha Centauri.

Alpha Centauri is the third-brightest star (that is, as seen from our place in space, and not counting the sun). Like the first- and second-brightest – Sirius and Canopus – it is a southern star. Indeed it’s much farther south than either of those, which is why it has no traditional name in our culture (except a rather faux-traditional one, Rigilkent).

The space diagram shows it at a steep southward angle from the sun. This angle (its declination -61°) means it doesn’t peep above the horizon till you go down to the latitude of northern Florida; to see it properly you might go south of Earth’s equator.

Then you would see in your telescope that it is a double star – one of the widest and easiest to “split.” Here is part of my diagram of the pair with which I used to fill a space in Astronomical Calendar 2016:

Proxima Centauri
Proxima Centauri
Sofia de Membiela

 Distance From Earth: 4.2 light years.

At 4.2 light years away Proxima Centauri is the nearest star to the sun, but as it is so small and dim it cannot be viewed with the naked eye.
The star can be found in the Centaurus constellation, a centaur is a Greek mythological half man half horse creature, proxima is Latin for next or nearest.  
The red dwarf Proxima Centauri is part of the three star Alpha Centauri system, the other two stars, Alpha Centauri A and B, are similar to our own sun. 


  

 Proxima centauri  might have the right conditions to support life, but it's 4.3 lightyears away and the trip would take conventional rockets thousands of years. 

 Proxima Centauri is a very small red dwarf with a radius of around 60,000 miles (97,000 km), which is around 14% the size of our sun.

 Red dwarfs emit far less energy than larger stars, its luminosity is less than one percent of that of our sun.
 
Laura Passera
Laura Passera
 
At 4.2 light years away Proxima Centauri is the nearest star to the sun, but as it is so small and dim it cannot be viewed with the naked eye.
The star can be found in the Centaurus constellation, a centaur is a Greek mythological half man half horse creature, proxima is Latin for next or nearest.
The red dwarf Proxima Centauri is part of the three star Alpha Centauri system, the other two stars, Alpha Centauri A and B, are similar to our own sun. 
Proxima Centauri is extremely distant from its two companions, orbiting them at a distance of around 1.2 trillion miles (1.9 trillion km).
Stars like our sun exist for a few billion years, red dwarfs like Proxima Centauri burn their fuel at a much lower rate and can therefore exist far longer.
In August 2016 it was announced that an Earth sized planet had been discovered orbiting the habitable zone around Proxima Centauri, the planet named Proxima b could possibly have liquid water on its surface 
Proxima b is the closest known planet outside our solar system.
The star Proxima Centauri was discovered in 1915 by the Scottish born astronomer Robert Innes.

Fotis Christodoulou
Fotis Christodoulou
 Proxima Centauri , or Alpha Centauri C, is a red dwarf, a small low-mass star, about 4.25 light-years (1.30 pc) from the Sun in the constellation of Centaurus. It was discovered in 1915 by the Scottish astronomer Robert Innes, the Director of the Union Observatory in South Africa, and is the nearest-known star to the Sun. With an apparent magnitude of 11.05, it is too faint to be seen with the naked eye. Proxima Centauri forms a third component of the Alpha Centauri trinary star system, currently with a separation of about 12,950 AU (1.94 trillion km) and an orbital period of 550,000 years. At present Proxima is 2.18° to the southwest of Alpha Centauri. 

Because of Proxima Centauri's proximity to Earth, its angular diameter can be measured directly. The star is about one-seventh the actual diameter of the Sun. It has a mass about an eighth of the Sun's mass , and its average density is about 33 times that of the Sun. Although it has a very low average luminosity, Proxima is a flare star that undergoes random dramatic increases in brightness because of magnetic activity. The star's magnetic field is created by convection throughout the stellar body, and the resulting flare activity generates a total X-ray emission similar to that produced by the Sun. The mixing of the fuel at Proxima Centauri's core through convection and its relatively low energy-production rate mean that it will be a main-sequence star for another four trillion years, or nearly 300 times the current age of the universe. 

In 2016, the European Southern Observatory announced the discovery of Proxima b, a planet orbiting the star at a distance of roughly 0.05 AU (7.5 million km) with an orbital period of approximately 11.2 Earth days. Its estimated mass is at least 1.3 times that of the Earth. The equilibrium temperature of Proxima b is estimated to be within the range of where water could exist as liquid on its surface, thus placing it within the habitable zone of Proxima Centauri, although because Proxima Centauri is a red dwarf and a flare star, whether it could support life is disputed. Previous searches for orbiting companions had ruled out the presence of brown dwarfs and supermassive planets. 

Adrian Chroust
Adrian Chroust
Proxima centauri:
Proxima centauri is a star in the state of a "red dwarf" which means that it is relatively cool. The star itself is about 4.25 light-years away. It is also called Alpha Centauri C which means that is a star in the star system Alpha Centauri beside the binary star Alpha Centauri AB which are two stars who orbit each other.
 

# data[].attributes.body
PROXIMA CENTAURI

At 4.2 light years away Proxima Centauri is the nearest star to the sun, but as it is so small and dim it cannot be viewed with the naked eye.

The star can be found in the Centaurus constellation, a centaur is a Greek mythological half man half horse creature, proxima is Latin for next or nearest.

The red dwarf Proxima Centauri is part of the three star Alpha Centauri system, the other two stars, Alpha Centauri A and B, are similar to our own sun.

Proxima Centauri is extremely distant from its two companions, orbiting them at a distance of around 1.2 trillion miles (1.9 trillion km).

Stars like our sun exist for a few billion years, red dwarfs like Proxima Centauri burn their fuel at a much lower rate and can therefore exist far longer.

In August 2016 it was announced that an Earth sized planet had been discovered orbiting the habitable zone around Proxima Centauri, the planet named Proxima b could possibly have liquid water on its surface.

Proxima b is the closest known planet outside our solar system.

The star Proxima Centauri was discovered in 1915 by the Scottish born astronomer Robert Innes.

# data[].attributes.body
The closest star to us, Proxima Centauri, and the planet that orbits it, Proxima b, are just 4.2 light-years away. The cool and faint red dwarf star is part of the Alpha Centauri system along with two larger stars. The planet Proxima b thrilled the astronomy community when it was discovered in August 2016, being not only the closest exoplanet to the solar system, but also terrestrial and the size of Earth. Even better, if the planet has an atmosphere, it could have surface temperatures of 86 degrees Fahrenheit (30º C) and possibly liquid water.

A new study has revealed that Proxima b is not the only thing that orbits our closest stellar neighbor. Astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile detected emissions from a dust belt around the small star. Similar to the asteroid belt in our own solar system, the ring of dust around Proxima Centauri could have particles ranging from dust grains less than a millimeter to asteroids that stretch multiple kilometers wide. The belt of cool dust, estimated at negative 382 degrees Farenheit (-230º C), is positioned one to four times as far from Proxima Centauri as the Earth is from the sun.

"The dust around Proxima is important because, following the discovery of the terrestrial planet Proxima b, it's the first indication of the presence of an elaborate planetary system, and not just a single planet, around the star closest to our sun," says lead author of the new study, Guillem Anglada of the Instituto de Astrofísica de Andalucía (CSIC) in Spain.

The ALMA data also suggests there may be another, fainter belt of dust about 10 times farther from Proxima Centauri than the inner ring. The outer ring, if it exists, would be an exciting feature for astronomers to study due to its frigid temperatures so far away from its small host star. These dust belts are the leftover debris that did not aggregate into planets, suggesting other fully-formed planets may be lurking in the system yet undiscovered. The findings are to be published in the Astrophysical Journal Letters.

"This result suggests that Proxima Centauri may have a multiple planet system with a rich history of interactions that resulted in the formation of a dust belt. Further study may also provide information that might point to the locations of as yet unidentified additional planets," said Anglada in a press release.

The Proxima Centauri system can be understood as a miniature version of our solar system. The red dwarf star is only about 1/7 the diameter of the sun, or about 1.5 times that of Jupiter. Its one confirmed planet, Proxima b, orbits much closer to the star than the dust belt, at just 2.5 million miles (4 million kilometers), which is only about 0.03 AU. The inner and outer dust belts of Proxima Centauri bear similarities to the asteroid belt between Mars and Jupiter and the Kuiper belt out beyond the orbit of Pluto.

# data[].attributes.body
Proxima Centauri (from Latin, meaning 'nearest star of Centaurus', or Alpha Centauri C, is a red dwarf, a small low-mass star, about 4.25 light-years (1.30 pc) from the Sun in the constellation of Centaurus. It was discovered in 1915 by the Scottish astronomer Robert Innes, the Director of the Union Observatory in South Africa, and is the nearest-known star to the Sun. With an apparent magnitude of 11.05, it is too faint to be seen with the naked eye. Proxima Centauri forms a third component of the Alpha Centauri trinary star system, currently with a separation of about 12,950 AU (1.94 trillion km) and an orbital period of 550,000 years. At present Proxima is 2.18° to the southwest of Alpha Centauri.

Because of Proxima Centauri's proximity to Earth, its angular diameter can be measured directly. The star is about one-seventh the actual diameter of the Sun. It has a mass about an eighth of the Sun's mass, and its average density is about 33 times that of the Sun. Although it has a very low average luminosity, Proxima is a flare star that undergoes random dramatic increases in brightness because of magnetic activity. The star's magnetic field is created by convection throughout the stellar body, and the resulting flare activity generates a total X-ray emission similar to that produced by the Sun. The mixing of the fuel at Proxima Centauri's core through convection and its relatively low energy-production rate mean that it will be a main-sequence star for another four trillion years,or nearly 300 times the current age of the universe.

# data[].attributes.body
The newly discovered planet, known as Proxima b, orbits the star Proxima Centauri, the closest star to the sun. Proxima Centauri is about 4.22 light-years — or 25 trillion miles (40 trillion kilometers) — from Earth.

That's a daunting distance. But an initiative announced this year aims to send superfast miniature probes to Proxima Centauri, on a journey that would take about 20 years. With the discovery of Proxima b, the founders of that initiative are even more eager to get going.

In 2015, NASA's New Horizon probe completed its 3-billion-mile (4.8 billion km) journey to Pluto after traveling for about 9.5 years. The spacecraft traveled at speeds topping 52,000 mph (84,000 km/h). At that rate, it would take New Horizons about 54,400 years to reach Proxima Centauri.

Last month, NASAS Juno probe reached speeds of about 165,000 mph (265,000 km/h) as it entered into orbit around Jupiter. At that rate, a probe could reach Proxima Centauri in about 17,157 years. (It should also be noted that there is currently no feasible way to accelerate a craft large enough to carry humans to those speeds.)

In other words, sending a probe to the nearest star system would not be easy.

The founders of the Breakthrough Starshot initiative want to send wafer-thin probes to Proxima Centauri at very high speeds. The plan calls for equipping these probes with thin sails, which would capture the energy imparted by a powerful Earth-based laser.

This laser would accelerate the probes to 20 percent the speed of light (about 134.12 million mph, or 215.85 million km/h), according to the program scientists. At that rate, the probes could reach Proxima Centauri in 20 to 25 years.

But first, scientists and engineers have to build the apparatus that will launch the tiny probes on their journey. In a news conference today (Aug. 24), Pete Worden, chairman of the Breakthrough Prize Foundation, said that a group of experts had convened earlier this week and discussed plans to build a prototype of the Starshot system. However, he added that the full-scale apparatus is at least 20 years off.

"We certainly hope that, within a generation, we can launch these nanoprobes," Worden said. "And so perhaps 20, 25 years from now, we could begin to launch them, and then they would travel for 25 years to get there."

He added that building the full-scale apparatus would likely cost about the same as building the Large Hadron Collider, the largest particle accelerator in the world; that project is estimated to have cost about $10 billion.

"Over the next decade, we will work with experts here at ESO [the European Southern Observatory] and elsewhere to get as much information as possible about the Proxima Centauri planet … even including whether it might bear life, prior to launching mankind's first probe towards the star," Worden said.

Worden said the Breakthrough Prize Foundation also hopes to "obtain similar data about the other nearby stars, Alpha Centauri A and B." (The two Alpha Centauri stars lie about 4.37 light-years from Earth; some astronomers think Proxima Centauri and the Alpha Centauri stars are part of the same system).

# data[].attributes.body
Proxima Centauri is the nearest star, and on August 24, 2016 astronomers announced it likely has a planet. This star is the nearest of a triple star system, which we on Earth see with the eye alone as the single star Alpha Centauri, visible from Earth’s Southern Hemisphere. They are about four light-years away.

The diagram above shows you where Alpha Centauri is, with respect to other nearby stars. It’s like that in the Nearest Stars section of the Astronomical Companion, but from a viewpoint that has moved closer and to a different angle so as to get a better look at Alpha Centauri. Included are stars within 12 light-years from the sun. The glows of light representing the stars are millions of times larger than the stars themselves, which would be microscopically small on this scale.

The grid serves to show the equatorial plane, and also the scale, the lines being 4 light-years apart. The slightly thicker line is the vernal equinox direction (the Earth-sun direction at March 20).

Imaginary stalks from the plane to the stars show how far north or south they are. I’ve cropped the picture so that some of the stars are off the top or bottom, but they are obscure stars you may not have heard of, with designations such as Lalande 21185, Luyten 726-8, DX Cancri. Most stars, including most of those near to us, are smaller than our sun – red dwarfs.

The exceptions near to us are Sirius, Procyon, and Alpha Centauri.

Alpha Centauri is the third-brightest star (that is, as seen from our place in space, and not counting the sun). Like the first- and second-brightest – Sirius and Canopus – it is a southern star. Indeed it’s much farther south than either of those, which is why it has no traditional name in our culture (except a rather faux-traditional one, Rigilkent).

The space diagram shows it at a steep southward angle from the sun. This angle (its declination -61°) means it doesn’t peep above the horizon till you go down to the latitude of northern Florida; to see it properly you might go south of Earth’s equator.

Then you would see in your telescope that it is a double star – one of the widest and easiest to “split.” Here is part of my diagram of the pair with which I used to fill a space in Astronomical Calendar 2016:

# data[].attributes.body
Sofia de Membiela

Distance From Earth: 4.2 light years.

At 4.2 light years away Proxima Centauri is the nearest star to the sun, but as it is so small and dim it cannot be viewed with the naked eye.

The star can be found in the Centaurus constellation, a centaur is a Greek mythological half man half horse creature, proxima is Latin for next or nearest.

The red dwarf Proxima Centauri is part of the three star Alpha Centauri system, the other two stars, Alpha Centauri A and B, are similar to our own sun.

Proxima centauri  might have the right conditions to support life, but it's 4.3 lightyears away and the trip would take conventional rockets thousands of years.

Proxima Centauri is a very small red dwarf with a radius of around 60,000 miles (97,000 km), which is around 14% the size of our sun.

Red dwarfs emit far less energy than larger stars, its luminosity is less than one percent of that of our sun.

# data[].attributes.body
At 4.2 light years away Proxima Centauri is the nearest star to the sun, but as it is so small and dim it cannot be viewed with the naked eye.

The star can be found in the Centaurus constellation, a centaur is a Greek mythological half man half horse creature, proxima is Latin for next or nearest.

The red dwarf Proxima Centauri is part of the three star Alpha Centauri system, the other two stars, Alpha Centauri A and B, are similar to our own sun.

Proxima Centauri is extremely distant from its two companions, orbiting them at a distance of around 1.2 trillion miles (1.9 trillion km).

Stars like our sun exist for a few billion years, red dwarfs like Proxima Centauri burn their fuel at a much lower rate and can therefore exist far longer.

In August 2016 it was announced that an Earth sized planet had been discovered orbiting the habitable zone around Proxima Centauri, the planet named Proxima b could possibly have liquid water on its surface

Proxima b is the closest known planet outside our solar system.

The star Proxima Centauri was discovered in 1915 by the Scottish born astronomer Robert Innes.

# data[].attributes.body
Proxima Centauri , or Alpha Centauri C, is a red dwarf, a small low-mass star, about 4.25 light-years (1.30 pc) from the Sun in the constellation of Centaurus. It was discovered in 1915 by the Scottish astronomer Robert Innes, the Director of the Union Observatory in South Africa, and is the nearest-known star to the Sun. With an apparent magnitude of 11.05, it is too faint to be seen with the naked eye. Proxima Centauri forms a third component of the Alpha Centauri trinary star system, currently with a separation of about 12,950 AU (1.94 trillion km) and an orbital period of 550,000 years. At present Proxima is 2.18° to the southwest of Alpha Centauri.

Because of Proxima Centauri's proximity to Earth, its angular diameter can be measured directly. The star is about one-seventh the actual diameter of the Sun. It has a mass about an eighth of the Sun's mass , and its average density is about 33 times that of the Sun. Although it has a very low average luminosity, Proxima is a flare star that undergoes random dramatic increases in brightness because of magnetic activity. The star's magnetic field is created by convection throughout the stellar body, and the resulting flare activity generates a total X-ray emission similar to that produced by the Sun. The mixing of the fuel at Proxima Centauri's core through convection and its relatively low energy-production rate mean that it will be a main-sequence star for another four trillion years, or nearly 300 times the current age of the universe.

In 2016, the European Southern Observatory announced the discovery of Proxima b, a planet orbiting the star at a distance of roughly 0.05 AU (7.5 million km) with an orbital period of approximately 11.2 Earth days. Its estimated mass is at least 1.3 times that of the Earth. The equilibrium temperature of Proxima b is estimated to be within the range of where water could exist as liquid on its surface, thus placing it within the habitable zone of Proxima Centauri, although because Proxima Centauri is a red dwarf and a flare star, whether it could support life is disputed. Previous searches for orbiting companions had ruled out the presence of brown dwarfs and supermassive planets.