HD 68375 (HR 3216) is a solitary[15] star in the northern circumpolar constellation Camelopardalis. It is faintly visible to the naked eye with an apparent magnitude of 5.54[2] and is estimated to be 289 light years distant.[1] However, it is receding with a heliocentric radial velocity of 4.33 km/s.[6]

HD 68375
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Camelopardalis
Right ascension 08h 19m 32.2891s[1]
Declination +75° 45′ 24.866″[1]
Apparent magnitude (V) 5.54±0.01[2]
Characteristics
Evolutionary stage Horizontal branch[3]
Spectral type G8 III[4]
B−V color index +0.9[5]
Astrometry
Radial velocity (Rv)4.33±0.16[6] km/s
Proper motion (μ) RA: +32.404 mas/yr[1]
Dec.: +15.893 mas/yr[1]
Parallax (π)11.2853 ± 0.0516 mas[1]
Distance289 ± 1 ly
(88.6 ± 0.4 pc)
Absolute magnitude (MV)+0.88[7]
Details
Mass1.91[8] M
Radius8.99[9] R
Luminosity49.4±0.5[10] L
Surface gravity (log g)2.77[11] cgs
Temperature5,078±5[9] K
Metallicity [Fe/H]−0.12±0.01[12] dex
Rotational velocity (v sin i)1.3±1.4[13] km/s
Age1.31[12] Gyr
Other designations
AG+75°385, BD+76°310, FK5 310, GC 11246, HD 68375, HIP 40793, HR 3216, SAO 6487[14]
Database references
SIMBADdata

HD 68375 has a stellar classification of G8 III,[4] indicating that it is a red giant. It is currently on the horizontal branch, generating energy via fusion inside a helium core. Specifically, it is a red clump star, at the cool end of the horizontal branch where stars with near-solar metallicity are found.[3] After approximately 1 billion years,[12] the star now has a radius of 9 R and an effective temperature of 5,078 K,[9] giving a yellow hue. Nevertheless, it has nearly double the mass of the Sun[8] and radiates at 49 times the luminosity of the Sun[10] from its enlarged photosphere. HD 68375 is slightly metal deficient with a metallicity 76% that of the Sun[12] and spins with a poorly constrained projected rotational velocity of 1.3 km/s.[13]

References

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  1. ^ a b c d e Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 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.
  3. ^ a b Ting, Yuan-Sen; Hawkins, Keith; Rix, Hans-Walter (3 May 2018). "A Large and Pristine Sample of Standard Candles across the Milky Way: ~100,000 Red Clump Stars with 3% Contamination". The Astrophysical Journal. 858 (1): L7. arXiv:1803.06650. Bibcode:2018ApJ...858L...7T. doi:10.3847/2041-8213/aabf8e. ISSN 0004-637X.
  4. ^ a b Cowley, A. P.; Bidelman, W. P. (February 1979). "MK spectral types for some F and G stars". Publications of the Astronomical Society of the Pacific. 91: 83. Bibcode:1979PASP...91...83C. doi:10.1086/130446. eISSN 1538-3873. ISSN 0004-6280.
  5. ^ Haggkvist, L.; Oja, T. (1970). "Results of BV photometry 1969-70 (Uppsala refractor)". Private Communication. Bibcode:1970Priv.........0H.
  6. ^ a b Soubiran, C.; Bienaymé, O.; Mishenina, T. V.; Kovtyukh, V. V. (9 January 2008). "Vertical distribution of Galactic disk stars". Astronomy & Astrophysics. 480 (1): 91–101. arXiv:0712.1370. Bibcode:2008A&A...480...91S. doi:10.1051/0004-6361:20078788. eISSN 1432-0746. ISSN 0004-6361.
  7. ^ 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.
  8. ^ 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. arXiv:astro-ph/0409024. Bibcode:2004ApJS..155..667D. doi:10.1086/424966. eISSN 1538-4365. ISSN 0067-0049.
  9. ^ a b c 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. ISSN 0004-6256.
  10. ^ a b 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.
  11. ^ Allende Prieto, C.; Lambert, D. L. (December 1999). "Fundamental parameters of nearby stars from the comparison with evolutionary calculations: masses, radii and effective temperatures". Astronomy and Astrophysics. 352: 555–562. arXiv:astro-ph/9911002. Bibcode:1999A&A...352..555A. ISSN 0004-6361.
  12. ^ a b c d Ting, Yuan-Sen; Rix, Hans-Walter (10 June 2019). "The Vertical Motion History of Disk Stars throughout the Galaxy". The Astrophysical Journal. 878 (1): 21. arXiv:1808.03278. Bibcode:2019ApJ...878...21T. doi:10.3847/1538-4357/ab1ea5. eISSN 1538-4357.
  13. ^ a b de Medeiros, J. R.; Mayor, M. (November 1999). "A catalog of rotational and radial velocities for evolved stars". Astronomy and Astrophysics Supplement Series. 139 (3): 433–460. Bibcode:1999A&AS..139..433D. doi:10.1051/aas:1999401. ISSN 0365-0138.
  14. ^ "HR+3216". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved July 13, 2022.
  15. ^ Eggleton, P. P.; Tokovinin, A. A. (11 September 2008). "A catalogue of multiplicity among bright stellar systems". Monthly Notices of the Royal Astronomical Society. 389 (2): 869–879. arXiv:0806.2878. Bibcode:2008MNRAS.389..869E. doi:10.1111/j.1365-2966.2008.13596.x. eISSN 1365-2966. ISSN 0035-8711.