Astronomy:HD 26755
  | |
| Observation data Epoch J2000.0 Equinox (celestial coordinates) | |
|---|---|
| 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[1] mas/yr Dec.: −25.942[1] mas/yr |
| Parallax (π) | 12.0207 ± 0.1939[1] mas |
| Distance | 271 ± 4 ly (83 ± 1 pc) |
| Absolute magnitude (MV) | +1.21[6] |
| Orbit[7] | |
| Primary | A |
| Companion | B |
| Period (P) | 1,658.7±2.9 d |
| Eccentricity (e) | 0.309±0.005 |
| Periastron epoch (T) | 2,453,848±5 JD |
| Argument of periastron (ω) (secondary) | 31.2±1.2° |
| Semi-amplitude (K1) (primary) | 6.10±0.04 km/s |
| Details | |
| Mass | 1.68[8] M☉ |
| Radius | 9.44±0.47[9] R☉ |
| Luminosity | 42.5±1.3[1] L☉ |
| Surface gravity (log g) | 2.58±0.11[10] cgs |
| Temperature | 4,717±92[10] K |
| Metallicity [Fe/H] | +0.17±0.05[10] dex |
| Rotational velocity (v sin i) | 1±1[11] km/s |
| Age | 2.13[8] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
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]
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 1 km/s,[11] which is poorly constrained.
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940 Gaia DR3 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 Appenzeller, Immo (April 1967). "MK Spectral Types for 185 Bright Stars". Publications of the Astronomical Society of the Pacific 79 (467): 102. doi:10.1086/128449. ISSN 0004-6280. Bibcode: 1967PASP...79..102A.
- ↑ Haggkvist, L.; Oja, T. (1970). "Results of BV photometry 1969-70 (Uppsala refractor)". Private Communication. Bibcode: 1970Priv.........0H.
- ↑ 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". Astronomy Letters 38 (5): 331–346. doi:10.1134/S1063773712050015. ISSN 1063-7737. Bibcode: 2012AstL...38..331A.
- ↑ 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. ISSN 0029-7704. Bibcode: 2012Obs...132..234G.
- ↑ 8.0 8.1 8.2 8.3 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. doi:10.1086/589654. ISSN 0067-0049. Bibcode: 2008ApJS..178...89D.
- ↑ 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. doi:10.1051/0004-6361:20035930. ISSN 0004-6361. Bibcode: 2004A&A...426..297K.
- ↑ 10.0 10.1 10.2 10.3 10.4 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. doi:10.3847/0004-637X/817/1/40. Bibcode: 2016ApJ...817...40F.
- ↑ 11.0 11.1 11.2 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. doi:10.1086/342613. ISSN 0004-637X. Bibcode: 2002ApJ...578..943D.
- ↑ "HD 26755". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+26755.
- ↑ 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. doi:10.1111/j.1365-2966.2008.13596.x. ISSN 0035-8711. Bibcode: 2008MNRAS.389..869E.
- ↑ 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. doi:10.1093/mnras/stx2219. ISSN 0035-8711. Bibcode: 2017MNRAS.472.3805G.
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