Gliese 832 c

Gliese 832 c
Extrasolar planet List of extrasolar planets
Parent star
Star Gliese 832
Constellation Grus
Right ascension (α) 21h 33m 33.9752s
Declination (δ) –49° 00′ 32.422″
Distance16.10 ly
(4.938 pc)
Spectral type M1.5V
Database references
Extrasolar Planets
Encyclopaedia		data
SIMBADdata
Exoplanet Archivedata
Open Exoplanet Cataloguedata

Gliese 832 c (also known as Gl 832 c or GJ 832 c) is an extrasolar planet located approximately 16 light-years away in the constellation of Grus, orbiting the star Gliese 832, a red dwarf.[1][2] The planet has an Earth Similarity Index of 0.81, one of the highest Earth Similarity Indices for any known extrasolar planet.[3] It is in its star's habitable zone.

To date, it is the second closest known potentially habitable exoplanet to Earth.[2] The closest potentially habitable exoplanet is Kapteyn b, at 13 light years distant.

Description

Gliese 832 c has a mass of approximately 5.4 times that of Earth. Its temperature is predicted to be relatively similar to Earth's, but is subject to significant swings as it orbits its star. The planet has a relatively high eccentricity, taking it very near to the predicted inner edge of the habitable zone. It has an orbital period of approximately 36 days.[3] The planet's average equilibrium temperature is predicted to be 253 kelvins (−20 °C),[3] but is estimated to vary from 233 kelvins (−40 °C) at apoastron to 280 kelvins (7 °C) at periastron.[4] However, because of its large mass, it may have a dense atmosphere, which could make it much hotter and more like the planet Venus, greatly reducing the chance for life.[5][6]

The orbit of GJ 832 c around its parent star, with the habitable zone boundaries shown. Planet c's orbit is rather eccentric and takes it in and out of the range of the habitable zone at different parts of its orbit, possibly leading to extreme seasons.[7]

The planet is a super-Earth mass planet orbiting in its star's habitable zone. Although it orbits its star much closer than the Earth orbits the Sun, it orbits a red dwarf, receiving approximately as much energy from it as the Earth does from its star.[2] It is not known whether Gliese 832 c transits its host star, something which would be required in order to detect any atmosphere the planet may have and determine its composition.

Discovery and impact

Gliese 832 c was discovered by an international team of astronomers led by Robert A. Wittenmyer.[2][3] It is the newest and closest to earth member of the top three most Earth-like worlds in the Habitable Exoplanets Catalog.[3]

The planet's discoverers described the planet as "the nearest best habitable world candidate so far".[8]

An artistic rendering of Gliese 832 c, made using the 3D software Blender 2.71. This depiction shows Gliese 832 c as a cloud-girdled greenhouse planet, with a dense atmosphere of water vapor and thick clouds obscuring the surface.

Further research may be done on Gliese 832 c to see if it is suitable for life.[6]

See also

References

  1. ↑ Wittenmyer, R. A. et al. (August 2014). "GJ 832c: A super-earth in the habitable zone". The Astrophysical Journal 791 (2). arXiv:1406.5587. Bibcode:2014ApJ...791..114W. doi:10.1088/0004-637X/791/2/114. 114.
  2. ↑ 2.0 2.1 2.2 2.3 Mike Wall (June 25, 2014), Nearby Alien Planet May Be Capable of Supporting Life, space.com, retrieved June 26, 2014
  3. ↑ 3.0 3.1 3.2 3.3 3.4 Abel Mendez Torres (June 25, 2014), A Nearby Super-Earth with the Right Temperature but Extreme Seasons
  4. ↑ <http://phl.upr.edu/press-releases/gliese832
  5. ↑ Nancy Atkinson (June 25, 2014), Nearby Super-Earth is Best Habitable Candidate So Far, Astronomers Say, retrieved June 26, 2014
  6. ↑ 6.0 6.1 David Snelling (June 26, 2014), Alien planet discovered! And it's not that far away
  7. ↑ <http://phl.upr.edu/press-releases/gliese832
  8. ↑ Hannah Osborne (June 25, 2014), Gliese 832 c: 'Best Habitable World Candidate' Discovered 16 Light Years Away, International Business Times, retrieved June 16, 2014

External links