HD 29678, also known as HR 1491, is a solitary star[14] located in the northern circumpolar constellation Camelopardalis. It is faintly visible to the naked eye as a yellowish-white hued point of light with an apparent magnitude of 5.95.[2] The object is located relatively close at a distance of 155 light-years[1] and it is drifting closer with a somewhat constrained heliocentric radial velocity of approximately −6.0 km/s.[6] At is current distance, HD 29678's brightness is diminished by 0.13 magnitudes due to interstellar extinction and it has an absolute magnitude of +2.60.[7] Its observed kinematics suggest that it is a member of the Pleiades supercluster.[15]

HD 29678
Location of HD 29678 on the map (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Camelopardalis
Right ascension 04h 48m 50.35317s[1]
Declination +75° 56′ 28.3916″[1]
Apparent magnitude (V) 5.95±0.01[2]
Characteristics
Evolutionary stage main sequence star[1]
Spectral type A9/F0 IV[3] or A6 V[4]
U−B color index −0.04[5]
B−V color index +0.27[5]
Astrometry
Radial velocity (Rv)−6.0±3.7[6] km/s
Proper motion (μ) RA: +37.476 mas/yr[1]
Dec.: −133.853 mas/yr[1]
Parallax (π)21.0142 ± 0.0265 mas[1]
Distance155.2 ± 0.2 ly
(47.59 ± 0.06 pc)
Absolute magnitude (MV)+2.60[7]
Details
Mass1.54[8] M
Radius1.73±0.09[9] R
Luminosity7.54+0.04
−0.06
[1] L
Surface gravity (log g)4.20+0.09
−0.07
[10] cgs
Temperature7,502±255[8] K
Metallicity [Fe/H]−0.26[11] dex
Rotational velocity (v sin i)120[12] km/s
Age146[8] Myr
Other designations
AG+75°168, BD+75°189, FK5 173, GC 5774, HD 29678, HIP 22361, HR 1491, SAO 5309, CCDM J04489+7557A, WDS J04488+7556A, TIC 140682376[13]
Database references
SIMBADdata

HD 29678 has a stellar classification of A9/F0 IV,[3] indicating that it is a slightly evolved star that has the characteristics of an A9 and F0 subgiant. Adams et al. (1935) yields a class of A6 V,[4] indicating that it is instead a hotter A-type main-sequence star that is generating energy via hydrogen fusion at is core. It has 1.54 times the mass of the Sun[8] and 1.73 times the radius of the Sun.[9] It radiates 7.54 times the luminosity of the Sun[1] from its photosphere at an effective temperature of 7,502 K.[8] The above characteristics more closely match a main sequence star and Gaia DR3 models the object as such.[1] HD 29678 is metal-deficient with an iron abundance of [Fe/H] = −0.26 or 55% of the Sun's[11] and it is estimated to be 146 million years old.[8] Like many hot stars it spins rapidly, having a projected rotational velocity of 120 km/s.[12]

HD 29678 has a 13th magnitude optical companion located 98.6" away along a position angle of 46°.[16] HD 29678 itself is an unrelated field star of the HIP 21974 cluster.[17]

References

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  1. ^ a b c d e f g h i 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.
  2. ^ a b 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. S2CID 17128864.
  3. ^ a b Cowley, A. P. (April 1976). "Spectral classification of the bright F stars". Publications of the Astronomical Society of the Pacific. 88: 95. Bibcode:1976PASP...88...95C. doi:10.1086/129905. eISSN 1538-3873. ISSN 0004-6280.
  4. ^ a b Adams, Walter S.; Joy, Alfred H.; Humason, Milton L.; Brayton, Ada Margaret (April 1935). "The Spectroscopic Absolute Magnitudes and Parallaxes of 4179 Stars". The Astrophysical Journal. 81: 187. Bibcode:1935ApJ....81..187A. doi:10.1086/143628. eISSN 1538-4357. ISSN 0004-637X. S2CID 121056016.
  5. ^ a b Imagawa, Fumihiko (February 1967). "Observational Results of Three-color Photometry for F-type Stars (II)". Memoirs of the College of Science, University of Kyoto. Series A. 31 (2): 93–100.
  6. ^ a b Kharchenko, N.V.; Scholz, R.-D.; Piskunov, A.E.; Röser, S.; Schilbach, E. (November 2007). "Astrophysical supplements to the ASCC-2.5: Ia. Radial velocities of ~55000 stars and mean radial velocities of 516 Galactic open clusters and associations". Astronomische Nachrichten. 328 (9): 889–896. arXiv:0705.0878. Bibcode:2007AN....328..889K. doi:10.1002/asna.200710776. eISSN 1521-3994. ISSN 0004-6337. S2CID 119323941.
  7. ^ a b Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331–346. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. eISSN 1562-6873. ISSN 1063-7737. S2CID 119257644.
  8. ^ a b c d e f David, Trevor J.; Hillenbrand, Lynne A. (12 May 2015). "The Ages of Early-type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets". The Astrophysical Journal. 804 (2): 146. arXiv:1501.03154. Bibcode:2015ApJ...804..146D. doi:10.1088/0004-637X/804/2/146. eISSN 1538-4357. S2CID 33401607.
  9. ^ a b Kervella, P.; Thévenin, F.; Di Folco, E.; Ségransan, D. (April 8, 2004). "The angular sizes of dwarf stars and subgiants: Surface brightness relations calibrated by interferometry". Astronomy & Astrophysics. 426 (1): 297–307. arXiv:astro-ph/0404180. Bibcode:2004A&A...426..297K. doi:10.1051/0004-6361:20035930. eISSN 1432-0746. ISSN 0004-6361. S2CID 6077801.
  10. ^ Stassun, Keivan G.; et al. (9 September 2019). "The Revised TESS Input Catalog and Candidate Target List". The Astronomical Journal. 158 (4): 138. arXiv:1905.10694. Bibcode:2019AJ....158..138S. doi:10.3847/1538-3881/ab3467. eISSN 1538-3881. hdl:1721.1/124721. S2CID 166227927.
  11. ^ a b Anders, F.; et al. (August 2019). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18". Astronomy & Astrophysics. 628: A94. arXiv:1904.11302. Bibcode:2019A&A...628A..94A. doi:10.1051/0004-6361/201935765. eISSN 1432-0746. ISSN 0004-6361. S2CID 131780028.
  12. ^ a b Danziger, I. J.; Faber, S. M. (May 1972). "Rotation of evolving A and F stars". Astronomy and Astrophysics. 18: 428. Bibcode:1972A&A....18..428D. ISSN 0004-6361. S2CID 118592077.
  13. ^ "HD 29678". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved November 13, 2023.
  14. ^ De Rosa, R. J.; et al. (26 November 2013). "The VAST Survey – III. The multiplicity of A-type stars within 75 pc". Monthly Notices of the Royal Astronomical Society. 437 (2): 1216–1240. arXiv:1311.7141. Bibcode:2014MNRAS.437.1216D. doi:10.1093/mnras/stt1932. eISSN 1365-2966. ISSN 0035-8711. S2CID 88503488.
  15. ^ Eggen, Olin J. (April 1992). "The Pleiades supercluster in FK 5". The Astronomical Journal. 103. American Astronomical Society: 1302. Bibcode:1992AJ....103.1302E. doi:10.1086/116142. ISSN 0004-6256. S2CID 120439628.
  16. ^ Mason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (December 2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog". The Astronomical Journal. 122 (6): 3466–3471. Bibcode:2001AJ....122.3466M. doi:10.1086/323920. ISSN 0004-6256. S2CID 119533755.
  17. ^ Cantat-Gaudin, T.; Jordi, C.; Vallenari, A.; Bragaglia, A.; Balaguer-Núñez, L.; Soubiran, C.; Bossini, D.; Moitinho, A.; Castro-Ginard, A.; Krone-Martins, A.; Casamiquela, L.; Sordo, R.; Carrera, R. (October 2018). "A Gaia DR2 view of the open cluster population in the Milky Way". Astronomy & Astrophysics. 618: A93. arXiv:1805.08726. Bibcode:2018A&A...618A..93C. doi:10.1051/0004-6361/201833476. ISSN 0004-6361. S2CID 56245426.