GJ 1132 b (also known as Gliese 1132 b) is an

exoplanet An exoplanet or extrasolar planet is a planet outside the Solar System. The first possible evidence of an exoplanet was noted in 1917 but was not recognized as such. The first confirmation of detection occurred in 1992. A different planet, init ...

orbiting the

red dwarf ''Red Dwarf'' is a British science fiction comedy franchise created by Rob Grant and Doug Naylor, which primarily consists of a television sitcom that aired on BBC Two between 1988 and 1999, and on Dave since 2009, gaining a cult following. T ...

star GJ 1132 from

Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ...

, in the constellation Vela. The planet is considered uninhabitable but cool enough to possess an

atmosphere An atmosphere () is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet retains an atmosphere when the gravity is great and the temperature of the atmosphere is low. A s ...

. GJ 1132 b was discovered by the MEarth-South array in Chile. It has been called "one of the most important planets ever discovered beyond the Solar System": Due to its relative proximity to Earth, telescopes should be able to determine the composition of its atmosphere, the speed of its winds and the color of its sunsets. This is due in part to the small diameter of its parent star (20% that of the Sun), which increases the effect on the star's light of its

transit Transit may refer to: Arts and entertainment Film * ''Transit'' (1979 film), a 1979 Israeli film * ''Transit'' (2005 film), a film produced by MTV and Staying-Alive about four people in countries in the world * ''Transit'' (2006 film), a 2006 ...

s. The planet's diameter is approximately 20% larger than that of the Earth and its mass is estimated at 1.6 times that of Earth, implying that it has an Earth-like rocky composition. GJ 1132 b orbits its star every 1.6 days at a distance of 1.4 million miles (2.24 million kilometres). The planet receives 19 times more stellar radiation than Earth. The

equilibrium temperature The planetary equilibrium temperature is a theoretical temperature that a planet would be if it were a black body being heated only by its parent star. In this model, the presence or absence of an atmosphere (and therefore any greenhouse effect) is ...

is estimated at for an Earth-like

albedo Albedo (; ) is the measure of the diffuse reflection of sunlight, solar radiation out of the total solar radiation and measured on a scale from 0, corresponding to a black body that absorbs all incident radiation, to 1, corresponding to a body ...

, or for a Venus-like albedo. The planet is likely to be hotter than Venus, as higher temperatures likely prevail at the surface if the planet has an atmosphere. It is possible that the night side of the planet is cooler, because it is presumed to be

tidally locked Tidal locking between a pair of co-orbiting astronomical body, astronomical bodies occurs when one of the objects reaches a state where there is no longer any net change in its rotation rate over the course of a complete orbit. In the case where ...

due to its proximity to its star; however, under most circumstances where an atmosphere is thick, it would be able to transfer heat to the far side.

Atmosphere

In April 2017, a hydrogen-dominated atmosphere was claimed to have been detected around GJ 1132 b. However, subsequent, more precise work ruled out the claim. Instead, in 2021 detection of a hazy hydrogen atmosphere without helium but with the admixture methane and

hydrogen cyanide Hydrogen cyanide, sometimes called prussic acid, is a chemical compound with the formula HCN and structure . It is a colorless, extremely poisonous, and flammable liquid that boils slightly above room temperature, at . HCN is produced on an ...

(implying substantial underlying free nitrogen in the mix, at around 8.9% of the atmosphere) was claimed. However, two subsequent studies found no evidence for molecular absorption in the HST WFC3 Spectrum of GJ 1132 b. Instead, the spectrum was found to be flat, which is more consistent with our current understanding of

photoevaporation Photoevaporation denotes the process where energetic radiation ionises gas and causes it to disperse away from the ionising source. This typically refers to an astrophysical context where ultraviolet electromagnetic radiation, radiation from hot st ...

Gallery

Artist%E2%80%99s_Impression_of_GJ_1132_b.jpg, An artist's impression of the exoplanet GJ 1132 b. Gj 1132b.jpg, An artist's impression of the exoplanet GJ 1132 b.

References

{{Sky, 10, 14, 51.100, -, 47, 09, 12.00 Exoplanets discovered in 2015

1132 Year 1132 ( MCXXXII) was a leap year starting on Friday (link will display the full calendar) of the Julian calendar. Events By place Levant * Summer – Imad al-Din Zengi, Seljuk governor (''atabeg'') of Aleppo and Mosul, marches ...

Vela (constellation) Transiting exoplanets

Atmosphere

Gallery

See also

References