Astronomy:HD 194012

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Short description: Star in the constellation Delphinus
HD 194012
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
Distance84.93 ± 0.05 ly
(26.04 ± 0.02 pc)
Absolute magnitude (MV)+4.06[6]
Details
Mass1.21+0.19−0.16[7] M
Radius1.18±0.04[7] R
Luminosity1.9[8] L
Surface gravity (log g)4.36[8] cgs
Temperature6,301±80[9] K
Metallicity [Fe/H]−0.06[8] dex
Rotational velocity (v sin i)5[10] km/s
Age1.06[11] Gyr
Other designations
BD+14°4275, GC 28343, GJ 789, HD 194012, HIP 100511, HR 7793, SAO 106042[12]
Database references
SIMBADdata

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 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. 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. Bibcode2021A&A...649A...1G.  Gaia EDR3 record for this source at VizieR.
  2. 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. Bibcode2000A&A...355L..27H. 
  3. 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. Bibcode2003AJ....126.2048G. 
  4. 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. Bibcode1964AJ.....69..215M. 
  5. 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. Bibcode2006AstL...32..759G. 
  6. 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. Bibcode2012AstL...38..331A. 
  7. 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. Bibcode2019AJ....158..138S. 
  8. 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. Bibcode2017AJ....153...21L. 
  9. 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. Bibcode2011A&A...530A.138C. 
  10. 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. Bibcode1967ApJ...150..551K. 
  11. 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. Bibcode2004ApJS..155..667D. 
  12. "HD 194012". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+194012. 
  13. 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. Bibcode2010PASP..122.1195T. 
  14. 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. Bibcode2016ApJ...826..171G.