Astronomy:Gliese 686

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Short description: Star in the Hercules constellation
Gliese 686
Observation data
Equinox J2000.0]] (ICRS)
Constellation Hercules[1]
Right ascension  17h 37m 53.347s[2]
Declination +18° 35′ 30.16″[2]
Apparent magnitude (V) 9.577[3]
Characteristics
Spectral type M1.0V[4]
B−V color index 1.530±0.015[1]
Astrometry
Radial velocity (Rv)−9.55±0.1[5] km/s
Proper motion (μ) RA: 926.638[2] mas/yr
Dec.: 984.455[2] mas/yr
Parallax (π)122.5546 ± 0.0176[2] mas
Distance26.613 ± 0.004 ly
(8.160 ± 0.001 pc)
Absolute magnitude (MV)10.08[1]
Details[4]
Mass0.426±0.017 M
Radius0.427±0.013 R
Luminosity0.0295±0.0007 L
Surface gravity (log g)4.87±0.07 cgs
Temperature3,656±51 K
Metallicity [Fe/H]−0.23±0.16 dex
Rotation38.732±0.286 d
Rotational velocity (v sin i)2.49 km/s
Other designations
BD+18 3421, HIP 86287, G 170-55, LHS 452, 2MASS J17375330+1835295[6]
Database references
SIMBADdata
ARICNSdata

Gliese 686 (GJ 686 / HIP 86287 / LHS 452)[6] is a star in the constellation of Hercules, with an apparent magnitude +9.577.[3] Although it is close to the Solar System – at 26.6 light-years – it is not the closest known star in its constellation, since Gliese 661 is 20.9 light years away.[7] The closest system to this star is the bright μ Herculis, at 4.5 light years. They are followed by GJ 1230 and Gliese 673, at 7.2 and 7.6 light years respectively.[8]

Gliese 686 is one of the many red dwarfs in the Solar System neighborhood with a spectral type of M1V,[3][6] and has an effective temperature of about 3600 K.[3] Its brightness in the visible spectrum is equal to 0.82% of that of the Sun,[9] while its total luminosity is equivalent to 2.7% that of the Sun,[10] since a significant amount of the radiation emitted by these stars is infrared invisible light. Considering only this last parameter, Gliese 686 is considerably brighter than other known red dwarfs; thus, it is 6.5 times more luminous than Ross 154 and 15 times more than Proxima Centauri, the closest star to the Solar System.

Gliese 686 has a radius approximately equal to half the solar radius. Its projected rotation speed is 2.5 km / s, its rotation period being equal to or less than 10.3 days.[11] It has a metallic content lower than that of the Sun; various studies estimate its index metallicity between -0.25 and -0.44.[11][12] It has an approximate mass between 45% and 49% of the solar mass[13] and is a star with characteristics comparable to that of Lacaille 9352.

Planetary system

Gliese 686 has one known super-Earth planet detected by radial velocity.[3] It is orbiting close to the host star with a separation of 0.091 AU (13.6 Gm) and an orbital period of 15.5 days. Since the inclination of its orbit is unknown, only a lower bound on its mass can be determined: it has at least 6.6 times the mass of the planet Earth.

The Gliese 686 planetary system[4]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b ≥6.624±0.432 M 0.091±0.001 15.530±0.0011 0.050±0.030

References

  1. 1.0 1.1 1.2 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode2012AstL...38..331A. 
  2. 2.0 2.1 2.2 2.3 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.
  3. 3.0 3.1 3.2 3.3 3.4 Affer, L.; Damasso, M.; Micela, G.; Poretti, E.; Scandariato, G.; Maldonado, J.; Lanza, A. F.; Covino, E. et al. (31 January 2019). "HADES RV program with HARPS-N at TNG. IX. A super-Earth around the M dwarf Gl686". Astronomy & Astrophysics 622: A193. doi:10.1051/0004-6361/201834868. ISSN 0004-6361. Bibcode2019A&A...622A.193A. 
  4. 4.0 4.1 4.2 Burt, Jennifer A.; Feng, Fabo; Holden, Bradford; Mamajek, Eric E.; Huang, Chelsea X.; Rosenthal, Mickey M.; Wang, Songhu; Paul Butler, R. et al. (2021), "A Collage of Small Planets from the Lick–Carnegie Exoplanet Survey: Exploring the Super-Earth and Sub-Neptune Mass Regime", The Astronomical Journal 161 (1): 10, doi:10.3847/1538-3881/abc2d0, Bibcode2021AJ....161...10B 
  5. Nidever, David L.; Marcy, Geoffrey W.; Butler, R. Paul; Fischer, Debra A.; Vogt, Steven S.; McGahee, C. E.; O'Donoghue, A. A.; Knox, E. R. (2002). "Radial Velocities for 889 Late-Type Stars". The Astrophysical Journal Supplement Series 141 (2): 503–522. doi:10.1086/340570. Bibcode2002ApJS..141..503N. 
  6. 6.0 6.1 6.2 "LHS 452". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=LHS+452. 
  7. "Closest stars". http://www.closeststars.com/. 
  8. "Stars within 15 light-years of Bonner Durchmusterung +18°3421 (The Internet Stellar Database)". http://www.stellar-database.com/Scripts/find_neighbors.exe?ID=122400&ly=15. 
  9. "Bonner Durchmusterung +18°3421 (The Internet Stellar Database)". http://www.stellar-database.com/Scripts/search_star.exe?Catalog=HIC&CatNo=86287. 
  10. Morales, J. C.; Ribas, I.; Jordi, C. (2008). "The effect of activity on stellar temperatures and radii". Astronomy and Astrophysics 478 (2): 507–512. doi:10.1051/0004-6361:20078324. pp. 507-512. Bibcode2008A&A...478..507M. http://cdsads.u-strasbg.fr/cgi-bin/nph-bib_query?2008A%26A...478..507M&db_key=AST&nosetcookie=1. 
  11. 11.0 11.1 Houdebine, E. R. (2010). "Observation and modelling of main-sequence star chromospheres - XIV. Rotation of dM1 stars". Monthly Notices of the Royal Astronomical Society 407 (3): 1657. doi:10.1111/j.1365-2966.2010.16827.x. pp. 1657–1673. Bibcode2010MNRAS.407.1657H. 
  12. Jenkins, J. S.; Ramsey, L. W.; Jones, H. R. A.; Pavlenko, Y.; Gallardo, J.; Barnes, J. R.; Pinfield, D. J. (2009). "Rotational Velocities for M Dwarfs". The Astrophysical Journal 704 (2): 975–988. doi:10.1088/0004-637X/704/2/975. Bibcode2009ApJ...704..975J. 
  13. Bonfils, Xavier; Delfosse, Xavier; Udry, Stéphane; Santos, Nuno C.; Forveille, Thierry; Ségransan, Damien (2005). "Metallicity of M dwarfs. I. A photometric calibration and the impact on the mass-luminosity relation at the bottom of the main sequence". Astronomy and Astrophysics 442 (2): 635–642. doi:10.1051/0004-6361:20053046. Bibcode2005A&A...442..635B. http://cdsads.u-strasbg.fr/cgi-bin/nph-bib_query?2005A%26A...442..635B&db_key=AST&nosetcookie=1.