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
Observation data
Epoch J2000      Equinox J2000
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 mas/yr[2]
Dec.: 984.455 mas/yr[2]
Parallax (π)122.5546 ± 0.0176 mas[2]
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 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: 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 half that of the Sun. 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

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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

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  1. ^ a b c Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. S2CID 119257644.
  2. ^ a b c d 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 Affer, L.; Damasso, M.; Micela, G.; Poretti, E.; Scandariato, G.; Maldonado, J.; Lanza, A. F.; Covino, E.; Rubio, A. Garrido (31 January 2019). "HADES RV program with HARPS-N at TNG. IX. A super-Earth around the M dwarf Gl686". Astronomy & Astrophysics. 622: A193. arXiv:1901.05338. Bibcode:2019A&A...622A.193A. doi:10.1051/0004-6361/201834868. ISSN 0004-6361. S2CID 118863481.
  4. ^ a b c Burt, Jennifer A.; Feng, Fabo; Holden, Bradford; Mamajek, Eric E.; Huang, Chelsea X.; Rosenthal, Mickey M.; Wang, Songhu; Paul Butler, R.; Vogt, Steven S.; Laughlin, Gregory; Henry, Gregory W.; Teske, Johanna K.; Wang, Sharon W.; Crane, Jeffrey D.; Shectman, Steve A. (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, arXiv:2011.08867, Bibcode:2021AJ....161...10B, doi:10.3847/1538-3881/abc2d0, S2CID 227013469
  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. arXiv:astro-ph/0112477. Bibcode:2002ApJS..141..503N. doi:10.1086/340570. S2CID 51814894.
  6. ^ a b c "LHS 452". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-09-02.
  7. ^ "Closest stars". closeststars.com. Archived from the original on 2023-04-11. Retrieved 2019-03-31.
  8. ^ "Stars within 15 light-years of Bonner Durchmusterung +18°3421 (The Internet Stellar Database)". stellar-database.com. Retrieved 2019-03-31.
  9. ^ "Bonner Durchmusterung +18°3421 (The Internet Stellar Database)". stellar-database.com. Archived from the original on 2023-04-11. Retrieved 2019-03-31.
  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. arXiv:0711.3523. Bibcode:2008A&A...478..507M. doi:10.1051/0004-6361:20078324. S2CID 16238033. pp. 507-512. Archived from the original on 2018-10-02. Retrieved 2019-03-31.
  11. ^ a b 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. Bibcode:2010MNRAS.407.1657H. doi:10.1111/j.1365-2966.2010.16827.x. pp. 1657–1673.
  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. arXiv:0908.4092. Bibcode:2009ApJ...704..975J. doi:10.1088/0004-637X/704/2/975. S2CID 119203469.
  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. arXiv:astro-ph/0503260. Bibcode:2005A&A...442..635B. doi:10.1051/0004-6361:20053046. S2CID 13900901.