Gliese 1132 b

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GJ 1132 b
Exoplanet Comparison GJ 1132 b.png
Size comparison of GJ 1132 b with Earth.
Discovery[3]
Discovered byMEarth-South Array Team
Discovery siteChile
Discovery dateMay 10, 2015 (announced)[1] November 12, 2015 (confirmed)[2]
Transit
Orbital characteristics
1.6 d
StarGliese 1132
Physical characteristics
Mean radius
1.2 REarth
Mass1.6 MEarth
Temperature410 K (137 °C; 278 °F)

Gliese 1132 b (also known as GJ 1132 b) is an exoplanet orbiting the red dwarf star Gliese 1132 40 light years (13 parsecs) from Earth,[3] in the constellation Vela. The planet is considered uninhabitable but cool enough to possess an atmosphere.[1] Gliese 1132 b was discovered by the MEarth-South array in Chile.[4]

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.[5][6][7] 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 transits. The planet's diameter is approximately 20% larger than that of the Earth[3] and its mass is estimated at 1.6 times that of Earth,[1] implying that it has an Earth-like rocky composition.[8] Gliese 1132 b orbits its star every 1.6 days at a distance of 1.4 million miles (2.24 million kilometres).[4]

The planet receives 19 times more stellar radiation than Earth.[3] The temperature of the top of its atmosphere is estimated at 500 °F (260 °C; 533 K). The planet is estimated to be hotter than Venus, as higher temperatures may prevail near the surface.[8] (cf. Atmosphere of Venus, Colonization of Venus) It is possible that one side of the planet is cooler, because it is presumed to be tidally locked 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 Gliese 1132 b.[9][10] However, subsequent, more precise work ruled out the claim.[11] Instead, in 2021 detection of a hazy hydrogen atmosphere without helium but with the admixture methane and hydrogen cyanide (implying substantial underlying free nitrogen in the mix, at around 8.9% of the atmosphere) was claimed.[12] 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,[13][14] which is more consistent with our current understanding of photoevaporation.

Gallery[]

See also[]

References[]

  1. ^ a b c Chu, Jennifer (November 11, 2015). "New exoplanet in our neighborhood". MIT News. Retrieved 2015-11-12.
  2. ^ NASA Exoplanet Archive New ticker slide 1
  3. ^ a b c d Berta-Thompson, Zachory K.; et al. (2015). "A rocky planet transiting a nearby low-mass star". Nature. 527 (7577): 204–207. arXiv:1511.03550. Bibcode:2015Natur.527..204B. doi:10.1038/nature15762. PMID 26560298. S2CID 4385619.
  4. ^ a b "Astronomers Eager to Get a Whiff of Newfound Venus-like Planet". Harvard–Smithsonian Center for Astrophysics. November 11, 2015. Retrieved 2015-11-12.
  5. ^ Sample, Ian. "Earth-like world could be 'most important planet found outside solar system'". The Guardian. Retrieved 2015-11-11.
  6. ^ Burgess, Matt. "Exoplanet GJ 1132b: the 'most important' ever found". Wired UK. Retrieved 2015-11-12.
  7. ^ "Getting Up Close and Personal with an Earth-Sized Exoplanet". The Kavli Foundation. November 11, 2015. Retrieved 2015-11-13.
  8. ^ a b Eva Botkin-Kowacki (2015-11-11). "Spotted: A rocky Earth-sized planet close by". The Christian Science Monitor.
  9. ^ "Atmosphere around super-Earth detected". Phys.Org. April 6, 2017. Retrieved April 6, 2017.
  10. ^ Southworth, John; et al. (2017). "Detection of the Atmosphere of the 1.6 M