Astronomy:HD 194012
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Short description: Star in the constellation Delphinus
| Observation data Epoch J2000.0 Equinox (celestial coordinates) | |
|---|---|
| Constellation | Delphinus |
| Right ascension | 20h 22m 52.3692s[1] |
| Declination | +14° 33′ 03.9513″[1] |
| Apparent magnitude (V) | 6.15±0.01[2] |
| Characteristics | |
| Spectral type | F7 V[3] |
| U−B color index | −0.07[4] |
| B−V color index | +0.51[4] |
| Astrometry | |
| Radial velocity (Rv) | 4.5±0.2[5] km/s |
| Proper motion (μ) | RA: +78.997[1] mas/yr Dec.: −7.143[1] mas/yr |
| Parallax (π) | 38.4009 ± 0.0233[1] mas |
| Distance | 84.93 ± 0.05 ly (26.04 ± 0.02 pc) |
| Absolute magnitude (MV) | +4.06[6] |
| Details | |
| Mass | 1.21+0.19−0.16[7] M☉ |
| Radius | 1.18±0.04[7] R☉ |
| Luminosity | 1.9[8] L☉ |
| Surface gravity (log g) | 4.36[8] cgs |
| Temperature | 6,301±80[9] K |
| Metallicity [Fe/H] | −0.06[8] dex |
| Rotational velocity (v sin i) | 5[10] km/s |
| Age | 1.06[11] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
HD 194012 (HR 7793; Gliese 789) is a star in the equatorial constellation Delphinus. It has an apparent magnitude of 6.15,[2] making it visible to the naked eye under ideal conditions. The star is relatively close at a distance of only 85 light years[1] but is receding with a heliocentric radial velocity of 4.5 km/s.[5]
HD 194012 has a stellar classification of F7 V,[3] indicating that it is an ordinary F-type main-sequence star. It has 121% the mass of the Sun[7] and is estimated to be a billion years old,[11] spinning with a projected rotational velocity of 5 km/s.[10] The star's diameter is 118% that of the Sun[7] and shines with a luminosity of 1.9 solar luminosity[8] from its photosphere at an effective temperature of 6,301 K,[9] giving a yellow white hue. HD 194012's metallicity is calculated to be 87% that of the Sun.[8]
A 2010 paper has identified a candidate substellar companion 12.78″ away along a position angle of 67.9°.[13] HD 194012 has been examined for infrared excess suggesting a debris disk but none was found.[14]
References
- ↑ 1.0 1.1 1.2 1.3 1.4 Brown, A. G. A. (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics 649: A1. doi:10.1051/0004-6361/202039657. Bibcode: 2021A&A...649A...1G. Gaia EDR3 record for this source at VizieR.
- ↑ 2.0 2.1 Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P. et al. (March 2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics 355: L27–L30. ISSN 0004-6361. Bibcode: 2000A&A...355L..27H.
- ↑ 3.0 3.1 Gray, R. O.; Corbally, C. J.; Garrison, R. F.; McFadden, M. T.; Robinson, P. E. (October 2003). "Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 Parsecs: The Northern Sample. I.". The Astronomical Journal 126 (4): 2048–2059. doi:10.1086/378365. ISSN 0004-6256. Bibcode: 2003AJ....126.2048G.
- ↑ 4.0 4.1 Marlborough, J. M. (March 1964). "Frequency of ultraviolet excess among late-type dwarfs in the solar neighbourhood.". The Astronomical Journal 69: 215. doi:10.1086/109258. ISSN 0004-6256. Bibcode: 1964AJ.....69..215M.
- ↑ 5.0 5.1 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. doi:10.1134/S1063773706110065. ISSN 1063-7737. Bibcode: 2006AstL...32..759G.
- ↑ Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation" (in en). Astronomy Letters 38 (5): 331–346. doi:10.1134/S1063773712050015. ISSN 1063-7737. Bibcode: 2012AstL...38..331A.
- ↑ 7.0 7.1 7.2 7.3 Stassun, Keivan G. et al. (9 September 2019). "The Revised TESS Input Catalog and Candidate Target List". The Astronomical Journal 158 (4): 138. doi:10.3847/1538-3881/ab3467. ISSN 0004-6256. Bibcode: 2019AJ....158..138S.
- ↑ 8.0 8.1 8.2 8.3 8.4 Luck, R. Earle (21 December 2016). "Abundances in the Local Region. II. F, G, and K Dwarfs and Subgiants". The Astronomical Journal 153 (1): 21. doi:10.3847/1538-3881/153/1/21. Bibcode: 2017AJ....153...21L.
- ↑ 9.0 9.1 Casagrande, L.; Schönrich, R.; Asplund, M.; Cassisi, S.; Ramírez, I.; Meléndez, J.; Bensby, T.; Feltzing, S. (June 2011). "New constraints on the chemical evolution of the solar neighbourhood and Galactic disc(s): Improved astrophysical parameters for the Geneva-Copenhagen Survey⋆". Astronomy & Astrophysics 530: A138. doi:10.1051/0004-6361/201016276. ISSN 0004-6361. Bibcode: 2011A&A...530A.138C.
- ↑ 10.0 10.1 Kraft, Robert P. (November 1967). "Studies of Stellar Rotation. V. The Dependence of Rotation on Age among Solar-Type Stars". The Astrophysical Journal 150: 551. doi:10.1086/149359. ISSN 0004-637X. Bibcode: 1967ApJ...150..551K.
- ↑ 11.0 11.1 Demarque, Pierre; Woo, Jong‐Hak; Kim, Yong‐Cheol; Yi, Sukyoung K. (December 2004). "Y 2 Isochrones with an Improved Core Overshoot Treatment". The Astrophysical Journal Supplement Series 155 (2): 667–674. doi:10.1086/424966. ISSN 1538-4357. Bibcode: 2004ApJS..155..667D.
- ↑ "HD 194012". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+194012.
- ↑ Tanner, Angelle M.; Gelino, Christopher R.; Law, Nicholas M. (October 2010). "A High-Contrast Imaging Survey ofSIM LitePlanet Search Targets". Publications of the Astronomical Society of the Pacific 122 (896): 1195–1206. doi:10.1086/656481. ISSN 0004-6280. Bibcode: 2010PASP..122.1195T.
- ↑ Gáspár, András; Rieke, George H.; Ballering, Nicholas (29 July 2016). "The Correlation Between Metallicity and Debris Disk Mass". The Astrophysical Journal 826 (2): 171. doi:10.3847/0004-637X/826/2/171. Bibcode: 2016ApJ...826..171G.
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