Sõda

MEEDIAVALVUR: algab „sõjalise erioperatsiooni“ teine etapp nimega „SÕDA“

Gliese 12 (GJ 12) is a red dwarf star located 39.7 light-years (12.2 parsecs) away in the constellation Pisces. It has about 24% the mass and 26% the radius of the Sun, and a temperature of about 3,296 K (3,023 °C; 5,473 °F). It is an inactive star and hosts one known exoplanet.[5]

Planetary system

The transiting exoplanet Gliese 12 b was discovered by TESS, and two independent studies confirming it as a planet were published in May 2024.[5][6] Gliese 12 b is similar in size to Earth and Venus, and completes an orbit around its star every 12.8 days. Its mass is poorly constrained but is known to be less than 4 times that of Earth.[5]

Along with the planets of TRAPPIST-1 and LHS 1140 b, Gliese 12 b is one of the nearest known relatively temperate transiting exoplanets, and so is a promising target for the James Webb Space Telescope to determine whether it has retained an atmosphere.[7] Gliese 12 b orbits slightly closer than the inner edge of its star's habitable zone, with an insolation between those of Earth and Venus.[6] Its equilibrium temperature, assuming an albedo of zero, is 315 K (42 °C; 107 °F); if it has an atmosphere, the surface temperature would be greater than this.[5]

The Gliese 12 planetary system[5]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b <3.87 M🜨 0.0668±0.0024 12.761408±0.000050 <0.50 89.194+0.059
−0.052
°
0.958+0.046
−0.048
 R🜨

References

  1. ^ "Finding the constellation which contains given sky coordinates". djm.cc. 2 August 2008. Archived from the original on 15 August 2019. Retrieved 23 May 2024.
  2. ^ a b c d e f Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  3. ^ a b c d e f g "GJ 12". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 23 May 2024.
  4. ^ Newton, Elisabeth R.; Charbonneau, David; et al. (January 2014). "Near-infrared Metallicities, Radial Velocities, and Spectral Types for 447 Nearby M Dwarfs". The Astronomical Journal. 147 (1): 20. arXiv:1310.1087. Bibcode:2014AJ....147...20N. doi:10.1088/0004-6256/147/1/20.
  5. ^ a b c d e f Kuzuhara, Masayuki; Fukui, Akihiko; et al. (23 May 2024). "Gliese 12 b: A Temperate Earth-sized Planet at 12 pc Ideal for Atmospheric Transmission Spectroscopy". The Astrophysical Journal Letters. 967 (2): L21. arXiv:2405.14708. Bibcode:2024ApJ...967L..21K. doi:10.3847/2041-8213/ad3642.
  6. ^ a b c Dholakia, Shishir; Palethorpe, Larissa; et al. (23 May 2024). "Gliese 12 b, a temperate Earth-sized planet at 12 parsecs discovered with TESS and CHEOPS". Monthly Notices of the Royal Astronomical Society. 531 (1): 1276–1293. arXiv:2405.13118. Bibcode:2024MNRAS.531.1276D. doi:10.1093/mnras/stae1152.
  7. ^ Reddy, Francis (23 May 2024). "NASA's TESS Finds Intriguing World Sized Between Earth, Venus". NASA. Archived from the original on 23 May 2024. Retrieved 23 May 2024.

Kommenteeri