Astronomy:Gliese 486

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Short description: Star in constellation of Virgo
Gliese 486 / Gar
Gliese486 SDSS9.png
Observation data
Equinox J2000.0]] (ICRS)
Constellation Virgo
Right ascension  12h 47m 56.62457s[1]
Declination +09° 45′ 05.0357″[1]
Apparent magnitude (V) 11.395
Characteristics
Evolutionary stage main sequence
Spectral type M3.5V[2]
Astrometry
Radial velocity (Rv)19.20±0.17[1] km/s
Proper motion (μ) RA: −1008.267[1] mas/yr
Dec.: −460.034[1] mas/yr
Parallax (π)123.7756 ± 0.0329[1] mas
Distance26.351 ± 0.007 ly
(8.079 ± 0.002 pc)
Details[3]
Mass0.323±0.015 M
Radius0.328±0.011 R
Luminosity0.01210±0.00023 L
Temperature3340±54 K
Metallicity [Fe/H]−0.15±0.13[4] dex
Rotation49.9±5.5 d[4]
Rotational velocity (v sin i)<2[5] km/s
Age1-8[4] Gyr
Other designations
Gar, GJ 486, HIP 62452, Wolf 437, TYC 882-1111-1, 2MASS J12475664+0945050[6]
Database references
SIMBADdata

Gliese 486, also known as Wolf 437 and formally named Gar, is a red dwarf star 26.4 light-years (8.1 parsecs) away in the constellation Virgo. It hosts one known exoplanet.[3]

Nomenclature

The designation Gliese 486 comes from the Gliese Catalogue of Nearby Stars. This was the 486th star listed in the first edition of the catalogue.

In August 2022, this planetary system was included among 20 systems to be named by the third NameExoWorlds project.[7] The approved names, proposed by a team from Spain , were announced in June 2023. Gliese 486 is named Gar and its planet is named Su, after the Basque words for "flame" and "fire".[8]

Properties

Gliese 486 has a surface temperature of 3340±54 K. Gliese 486 is similar to the Sun in its concentration of heavy elements, with a metallicity Fe/H index of 0.07±0.16. It was suspected to be a flare star,[9] although measurements available in 2019 did not reveal any flares.[10] The chemical makeup of the star is unremarkable and consistent with solar abundances or being slightly metal-poor.[4]

The star has an unremarkable magnetic field in the chromosphere of about 1.6 kilogauss.[5] It is rotating very slowly and is likely to be very old, belonging kinematically to the old thin disk of the Milky Way.[11]

Multiplicity surveys did not detect any stellar companions to Gliese 486 as of 2020.[12]

Planetary system

Artistic impression of the surface of the hot super-Earth Gliese 486b.

In 2021, one planet, named Gliese 486 b (ja), was discovered on a tight, circular orbit.[3] It represents a rare class of rocky exoplanet suitable for spectroscopic characterization in the near future[13] by the James Webb Space Telescope.[14] As of 2022, no hydrogen or steam dominated atmosphere was detected, although a secondary planetary atmosphere with a higher molecular weight remains a possibility.[15] Observations by JWST announced in 2023 detected signs of water vapor, but it is unclear if this is from the planet's atmosphere or from its host star.[16][17]

The Gliese 486 planetary system[3]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b / Su 2.82+0.11−0.12 M 0.01734+0.00026−0.00027 1.467119+0.000031−0.000030 <0.05 88.4+1.1−1.4° 1.305+0.063−0.067 R

References

  1. 1.0 1.1 1.2 1.3 1.4 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940  Gaia DR3 record for this source at VizieR.
  2. Bozhinova, I.; Helling, Ch.; Scholz, A. (2014), "Planetary host stars: Evaluating uncertainties in cool model atmospheres", Monthly Notices of the Royal Astronomical Society 450: 160–182, doi:10.1093/mnras/stv613, Bibcode2015MNRAS.450..160B 
  3. 3.0 3.1 3.2 3.3 Trifonov, T. et al. (2021), "A nearby transiting rocky exoplanet that is suitable for atmospheric investigation", Science 371 (6533): 1038–1041, doi:10.1126/science.abd7645, PMID 33674491, Bibcode2021Sci...371.1038T 
  4. 4.0 4.1 4.2 4.3 Caballero, J. A. et al. (2022), "A detailed analysis of the Gl 486 planetary system", Astronomy & Astrophysics 665: A120, doi:10.1051/0004-6361/202243548, Bibcode2022A&A...665A.120C 
  5. 5.0 5.1 Moutou, Claire; Hébrard, Élodie M.; Morin, Julien; Malo, Lison; Fouqué, Pascal; Torres-Rivas, Andoni; Martioli, Eder; Delfosse, Xavier et al. (2017), "SPIRou input catalogue: Activity, rotation and magnetic field of cool dwarfs", Monthly Notices of the Royal Astronomical Society 472 (4): 4563–4586, doi:10.1093/mnras/stx2306, Bibcode2017MNRAS.472.4563M 
  6. "Wolf 437". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=Wolf+437. 
  7. "List of ExoWorlds 2022". IAU. 8 August 2022. https://www.nameexoworlds.iau.org/2022exoworlds. 
  8. "2022 Approved Names". IAU. https://www.nameexoworlds.iau.org/2022approved-names. 
  9. O'Donoghue, D.; Koen, C.; Kilkenny, D.; Stobie, R. S.; Koester, D.; Bessell, M. S.; Hambly, N.; MacGillivray, H. (2003), "The DA+d Me eclipsing binary EC13471-1258: its cup runneth over ... Just", Monthly Notices of the Royal Astronomical Society 345 (2): 506–528, doi:10.1046/j.1365-8711.2003.06973.x, Bibcode2003MNRAS.345..506O 
  10. Vida, Krisztián; Leitzinger, Martin; Kriskovics, Levente; Seli, Bálint; Odert, Petra; Kovács, Orsolya Eszter; Korhonen, Heidi; Van Driel-Gesztelyi, Lidia (2019), "The quest for stellar coronal mass ejections in late-type stars", Astronomy & Astrophysics 623: A49, doi:10.1051/0004-6361/201834264 
  11. Browning, Matthew K.; Basri, Gibor; Marcy, Geoffrey W.; West, Andrew A.; Zhang, Jiahao (2010), "Rotation and Magnetic Activity in a Sample of M-Dwarfs", The Astronomical Journal 139 (2): 504, doi:10.1088/0004-6256/139/2/504, Bibcode2010AJ....139..504B 
  12. Lamman, Claire; Baranec, Christoph; Berta-Thompson, Zachory K.; Law, Nicholas M.; Schonhut-Stasik, Jessica; Ziegler, Carl; Salama, Maïssa; Jensen-Clem, Rebecca et al. (2020), "Robo-AO M-dwarf Multiplicity Survey: Catalog", The Astronomical Journal 159 (4): 139, doi:10.3847/1538-3881/ab6ef1, Bibcode2020AJ....159..139L 
  13. Hot Super-Earth Discovered 26 Light-Years Away
  14. Newfound exoplanet could be 'Rosetta Stone' for studies of alien atmospheres
  15. Ridden-Harper, Andrew; Nugroho, Stevanus; Flagg, Laura; Jayawardhana, Ray; Turner, Jake D.; Ernst de Mooij; MacDonald, Ryan; Deibert, Emily et al. (2023), "High-resolution Transmission Spectroscopy of the Terrestrial Exoplanet GJ 486b", The Astronomical Journal 165 (4): 170, doi:10.3847/1538-3881/acbd39, Bibcode2023AJ....165..170R 
  16. Moran, Sarah E. et al. (May 2023). "High Tide or Rip-Tide on the Cosmic Shoreline? A Water-Rich Atmosphere or Stellar Contamination for the Warm Super-Earth GJ 486b from JWST Observations". The Astrophysical Journal Letters 948 (1): L11. doi:10.3847/2041-8213/accb9c. Bibcode2023ApJ...948L..11M. 
  17. "Webb Finds Water Vapor, But From a Rocky Planet or Its Star?". STScI. 1 May 2023. https://webbtelescope.org/contents/news-releases/2023/news-2023-120. 

Coordinates: Sky map 12h 47m 56.6249s, +09° 45′ 05.0319″