BD+14 4559 is a star with an exoplanetary companion in the northern constellation of Pegasus. During the 2019 NameExoWorlds campaign, the star was named Solaris by Poland after a 1961 science fiction novel about an ocean-covered exoplanet by Polish writer Stanisław Lem.[6] With an apparent visual magnitude of 9.78,[2] the star is too faint to be viewed with the naked eye. The system is located at a distance of 161 light-years from the Sun based on parallax measurements, but is drifting closer with a radial velocity of −44 km/s.[1] It is a high proper motion star,[3] traversing the celestial sphere at an angular rate of 0.234″ yr−1.[7]

BD+14 4559 / Solaris
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Pegasus
Right ascension 21h 13m 35.9901s[1]
Declination +14° 41′ 21.7846″[1]
Apparent magnitude (V) 9.78[2]
Characteristics
Spectral type K2V[3]
B−V color index 1.611±0.218
V−R color index 0.68[2]
R−I color index 0.50[2]
Astrometry
Radial velocity (Rv)−44.30±0.30[1] km/s
Proper motion (μ) RA: 233.993±0.057 mas/yr[1]
Dec.: −0.275±0.056 mas/yr[1]
Parallax (π)20.2337 ± 0.0345 mas[1]
Distance161.2 ± 0.3 ly
(49.42 ± 0.08 pc)
Absolute magnitude (MV)6.14
Absolute bolometric
magnitude
 (Mbol)
5.56[3]
Details
Mass0.82±0.02[4] M
Radius0.78±0.02[4] R
Luminosity0.32±0.01[4] L
Luminosity (bolometric)0.4786[3] L
Surface gravity (log g)4.57±0.03[4] cgs
Temperature4,948±25[4] K
Metallicity [Fe/H]0.10±0.07[3] dex
Age6.9±4.2[4] Gyr
Other designations
Solaris, AG+14 2370, BD+14 4559, HIP 104780, PPM 139779, LTT 16221[5]
Database references
SIMBADdata
Exoplanet Archivedata

This is an ordinary K-type main sequence star with a stellar classification of K2V.[3] The age of the star is poorly constrained, but is estimated to be roughly seven billion years. It has 82% of the mass and 78% of the radius of the Sun.[4] The star is radiating 48%[3] of the net luminosity of the Sun from its photosphere at an effective temperature of 4,948 K.[4] It has a higher metallicity – the abundance of elements of higher atomic number than helium – compared to the Sun.[3]

Planetary system edit

On June 10, 2009, an exoplanet (Pirx) was found in orbit by Niedzielski et al. using the Hobby-Eberly Telescope.[3] It has a minimum mass of one and a half Jupiter masses (MJ). The orbit of this object is highly eccentric and it spends 65% of its orbital period in the star's habitable zone.[8] A 2020 analysis of data from the Gaia mission has set a 3-sigma upper limit to its mass of 49.83 MJ.[9] There may be an undetected second planet orbiting the star, however this is unconfirmed.[3]

The BD+14 4559 planetary system[3][9]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b / Pirx >1.52 ± 0.19 MJ 0.777 268.94 ± 0.99 0.29 ± 0.03 >1.769°
c (unconfirmed) >2.4 MJ >2.3 800?

See also edit

References edit

  1. ^ a b c d e f Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  2. ^ a b c d 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.
  3. ^ a b c d e f g h i j k Niedzielski, A.; et al. (2009). "Substellar-mass Companions to the K-dwarf BD+14 4559 and the K-giants HD 240210 and BD+20 2457". The Astrophysical Journal. 707 (1): 768–777. arXiv:0906.1804. Bibcode:2009ApJ...707..768N. doi:10.1088/0004-637X/707/1/768. S2CID 16877069.
  4. ^ a b c d e f g h Bonfanti, A.; et al. (2016). "Age consistency between exoplanet hosts and field stars". Astronomy & Astrophysics. 585: 14. arXiv:1511.01744. Bibcode:2016A&A...585A...5B. doi:10.1051/0004-6361/201527297. S2CID 53971692. A5.
  5. ^ "9 Cet". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2021-11-12.
  6. ^ "Approved names". NameExoworlds. Retrieved 2020-01-02.
  7. ^ Lépine, Sébastien; Shara, Michael M. (March 2005). "A Catalog of Northern Stars with Annual Proper Motions Larger than 0.15" (LSPM-NORTH Catalog)". The Astronomical Journal. 129 (3): 1483–1522. arXiv:astro-ph/0412070. Bibcode:2005AJ....129.1483L. doi:10.1086/427854. S2CID 2603568.
  8. ^ Hinkel, Natalie R.; Kane, Stephen R. (September 2013). "Habitability of Exomoons at the Hill or Tidal Locking Radius". The Astrophysical Journal. 774 (1): 10. arXiv:1307.4760. Bibcode:2013ApJ...774...27H. doi:10.1088/0004-637X/774/1/27. S2CID 5072506. 27.
  9. ^ a b Kiefer, F.; et al. (2021). "Determining the true mass of radial-velocity exoplanets with Gaia". Astronomy & Astrophysics. 645: A7. arXiv:2009.14164. Bibcode:2021A&A...645A...7K. doi:10.1051/0004-6361/202039168. S2CID 221995447.