HD 203842
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Equuleus |
Right ascension | 21h 24m 24.56s[1] |
Declination | +10° 10′ 27.27″[1] |
Apparent magnitude (V) | 6.32±0.01[2] |
Characteristics | |
Spectral type | F5 III[3] |
U−B color index | +0.13[4] |
B−V color index | +0.47[4] |
Astrometry | |
Radial velocity (Rv) | −21.8±3.6[5] km/s |
Proper motion (μ) | RA: +75.072 mas/yr[1] Dec.: +20.436 mas/yr[1] |
Parallax (π) | 9.9662 ± 0.0646 mas[1] |
Distance | 327 ± 2 ly (100.3 ± 0.7 pc) |
Absolute magnitude (MV) | 1.21 |
Details | |
Mass | 2[6] M☉ |
Radius | 3.87+0.23 −0.22[7] R☉ |
Luminosity | 30.5[8] L☉ |
Temperature | 6,271±42[9] K |
Metallicity [Fe/H] | +0.19+0.04 −0.05[7] dex |
Rotational velocity (v sin i) | 81[10] km/s |
Age | 1.24[6] Gyr |
Other designations | |
Database references | |
SIMBAD | data |
HD 203842 (HR 8191) is a solitary star in the constellation Equuleus. With an apparent magnitude of 6.32, it's barely visible to the naked eye under ideal conditions. The star is located 327 light-years (100 parsecs) based on parallax, but is drifting closer with a heliocentric radial velocity of −33 km/s. HD 203842 is part of the Hyades Stream,[11] which is not related to the Hyades Cluster.
HD 203842 has 1.85 times the Sun's mass, but at an age of 1.25 billion years, has expanded to 4 times the Sun's radius. It radiates at 24 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 6,333 K. Despite it being classified as a giant star, it has a projected rotational velocity of 50 km/s, and 120% the abundance of heavy metals compared to the Sun.
References
- ^ a b c d 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.
- ^ Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (March 2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27–L30. Bibcode:2000A&A...355L..27H. ISSN 0004-6361.
- ^ Roman, Nancy G. (December 1955). "A Catalogue of High-Velocity Stars". The Astrophysical Journal Supplement Series. 2: 195. Bibcode:1955ApJS....2..195R. doi:10.1086/190021. eISSN 1538-4365. ISSN 0067-0049.
- ^ a b Johnson, H. L.; Mitchell, R. I.; Iriarte, B.; Wisniewski, W. Z. (1966). "UBVRIJKL Photometry of the Bright Stars". Communications of the Lunar and Planetary Laboratory. 4: 99–110. Bibcode:1966CoLPL...4...99J.
- ^ Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35,495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. eISSN 1562-6873. ISSN 1063-7737. S2CID 119231169.
- ^ a b Demarque, Pierre; Woo, Jong‐Hak; Kim, Yong‐Cheol; Yi, Sukyoung K. (December 2004). "Y2 Isochrones with an Improved Core Overshoot Treatment". The Astrophysical Journal Supplement Series. 155 (2): 667–674. Bibcode:2004ApJS..155..667D. doi:10.1086/424966. eISSN 1538-4365. ISSN 0067-0049.
- ^ a b Bochanski, John J.; Faherty, Jacqueline K.; Gagné, Jonathan; Nelson, Olivia; Coker, Kristina; Smithka, Iliya; Desir, Deion; Vasquez, Chelsea (13 March 2018). "Fundamental Properties of Co-moving Stars Observed by Gaia". The Astronomical Journal. 155 (4): 149. arXiv:1801.00537. Bibcode:2018AJ....155..149B. doi:10.3847/1538-3881/aaaebe. ISSN 0004-6256. S2CID 119256051.
- ^ McDonald, I.; Zijlstra, A. A.; Boyer, M. L. (21 November 2012). "Fundamental parameters and infrared excesses of Hipparcos stars: Parameters and IR excesses from Hipparcos". Monthly Notices of the Royal Astronomical Society. 427 (1): 343–357. arXiv:1208.2037. Bibcode:2012MNRAS.427..343M. doi:10.1111/j.1365-2966.2012.21873.x. eISSN 1365-2966. ISSN 0035-8711.
- ^ Luck, R. Earle (25 August 2015). "Abundances in the Local Region. I. G and K Giants". The Astronomical Journal. 150 (3): 88. arXiv:1507.01466. Bibcode:2015AJ....150...88L. doi:10.1088/0004-6256/150/3/88. eISSN 1538-3881. ISSN 0004-6256. S2CID 118505114.
- ^ Solano, E.; Fernley, J. (April 1997). "Spectroscopic survey of δ Scuti stars". Astronomy and Astrophysics Supplement Series. 122 (1): 131–147. Bibcode:1997A&AS..122..131S. doi:10.1051/aas:1997329. eISSN 1286-4846. ISSN 0365-0138.
- ^ Montes, D.; López-Santiago, J.; Gálvez, M. C.; Fernández-Figueroa, M. J.; De Castro, E.; Cornide, M. (1 November 2001). "Late-type members of young stellar kinematic groups - I. Single stars". Monthly Notices of the Royal Astronomical Society. 328: 45–63. Bibcode:2001MNRAS.328...45M. doi:10.1046/j.1365-8711.2001.04781.x. ISSN 0035-8711. S2CID 55727428.