HD 26755, also known as HR 1313, is a spectroscopic binary[11][13] located in the northern circumpolar constellation Camelopardalis, the giraffe. It has an apparent magnitude of 5.72,[2] making it faintly visible to the naked eye under ideal conditions. Gaia DR3 parallax measurements place the system at a distance of 271 light years[1] and is currently drifitng closer with a heliocentric radial velocity of −38 km/s.[5] At its current distance, HD 26755's brightness is diminished by 0.19 magnitudes due to interstellar dust.[14]

HD 26755
Location of HD 26755 on the map (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Camelopardalis
Right ascension 04h 17m 08.09353s[1]
Declination +57° 51′ 37.1513″[1]
Apparent magnitude (V) 5.72±0.01[2]
Characteristics
Spectral type K1 III[3]
B−V color index +1.09[4]
Astrometry
Radial velocity (Rv)−38.2±1.6[5] km/s
Proper motion (μ) RA: +29.108 mas/yr[1]
Dec.: −25.942 mas/yr[1]
Parallax (π)12.0207 ± 0.1939 mas[1]
Distance271 ± 4 ly
(83 ± 1 pc)
Absolute magnitude (MV)+1.21[6]
Orbit[7]
PrimaryA
CompanionB
Period (P)1,658.7±2.9 d
Eccentricity (e)0.309±0.005
Periastron epoch (T)2,453,848±JD
Argument of periastron (ω)
(secondary)
31.2±1.2°
Semi-amplitude (K1)
(primary)
6.10±0.04 km/s
Details
Mass1.68[8] M
Radius9.44±0.47[9] R
Luminosity42.5±1.3[1] L
Surface gravity (log g)2.58±0.11[10] cgs
Temperature4,717±92[10] K
Metallicity [Fe/H]+0.17±0.05[10] dex
Rotational velocity (v sin i)1±1[11] km/s
Age2.13[8] Gyr
Other designations
AG+57°460, BD+57°787, GC 5139, HD 26755, HIP 19983, HR 1313, SAO 24514[12]
Database references
SIMBADdata

The visible component is an evolved red giant with a stellar classification of K1 III.[3] It is estimated to be 2.13 billion years old,[8] enough time for the star to exhaust its core hydrogen and evolve to become a red giant. It has cooled and expanded to 9.4 times the Sun's radius. It has 1.68 times the mass of the Sun[8] and radiates 42.5 times the luminosity of the Sun[1] from its enlarged photosphere at an effective temperature of 4,717 K,[10] giving it an orange hue when viewed in the night sky. HD 26755 is a metal enriched star with an iron abundance 48% greater than the Sun.[10] It spins slowly with a projected rotational velocity of km/s,[11] which is poorly constrained.

References

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  1. ^ a b c d e f g 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.
  3. ^ a b Appenzeller, Immo (April 1967). "MK Spectral Types for 185 Bright Stars". Publications of the Astronomical Society of the Pacific. 79 (467): 102. Bibcode:1967PASP...79..102A. doi:10.1086/128449. eISSN 1538-3873. ISSN 0004-6280.
  4. ^ Haggkvist, L.; Oja, T. (1970). "Results of BV photometry 1969-70 (Uppsala refractor)". Private Communication. Bibcode:1970Priv.........0H.
  5. ^ a b 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.
  6. ^ 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.
  7. ^ Griffin, R. F. (August 2012). "Spectroscopic binary orbits from photoelectric radial velocities - Paper 225: HR 1313, HR 3567, HR 3907, and HR 6239; with a note on delta Boo, HD 146815, 64 Aql, and 75 Dra". The Observatory. 132 (4): 234–252. Bibcode:2012Obs...132..234G. ISSN 0029-7704.
  8. ^ a b c d Dotter, Aaron; Chaboyer, Brian; Jevremović, Darko; Kostov, Veselin; Baron, E.; Ferguson, Jason W. (September 2008). "The Dartmouth Stellar Evolution Database". The Astrophysical Journal Supplement Series. 178 (1): 89–101. arXiv:0804.4473. Bibcode:2008ApJS..178...89D. doi:10.1086/589654. eISSN 1538-4365. ISSN 0067-0049.
  9. ^ Kervella, P.; Thévenin, F.; Di Folco, E.; Ségransan, D. (October 2004). "The angular sizes of dwarf stars and subgiants". 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.
  10. ^ a b c d e Feuillet, Diane K.; Bovy, Jo; Holtzman, Jon; Girardi, Léo; MacDonald, Nick; Majewski, Steven R.; Nidever, David L. (20 January 2016). "Determining Ages of APOGEE Giants with Known Distances". The Astrophysical Journal. 817 (1): 40. arXiv:1511.04088. Bibcode:2016ApJ...817...40F. doi:10.3847/0004-637X/817/1/40. eISSN 1538-4357.
  11. ^ a b c De Medeiros, J. R.; Da Silva, J. R. P.; Maia, M. R. G. (20 October 2002). "The Rotation of Binary Systems with Evolved Components". The Astrophysical Journal. 578 (2): 943–950. arXiv:astro-ph/0207288. Bibcode:2002ApJ...578..943D. doi:10.1086/342613. eISSN 1538-4357. ISSN 0004-637X.
  12. ^ "HD 26755". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 14 December 2022.
  13. ^ 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.
  14. ^ Gontcharov, George A.; Mosenkov, Aleksandr V. (28 September 2017). "Verifying reddening and extinction for Gaia DR1 TGAS main sequence stars". Monthly Notices of the Royal Astronomical Society. 472 (4): 3805–3820. arXiv:1709.01160. Bibcode:2017MNRAS.472.3805G. doi:10.1093/mnras/stx2219. eISSN 1365-2966. ISSN 0035-8711.