HD 26670
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Camelopardalis |
| Right ascension | 04h 16m 53.55609s[1] |
| Declination | +61° 50′ 59.9671″[1] |
| Apparent magnitude (V) | 5.70[2] |
| Characteristics | |
| Evolutionary stage | main sequence[3] |
| Spectral type | B7 V[4] or B5 Vn[5] |
| U−B color index | −0.52[6] |
| B−V color index | −0.14[2][6] |
| Astrometry | |
| Radial velocity (Rv) | 0.4±2.8[7] km/s |
| Proper motion (μ) | RA: +6.504 mas/yr[1] Dec.: −20.592 mas/yr[1] |
| Parallax (π) | 6.6445 ± 0.0565 mas[1] |
| Distance | 491 ± 4 ly (151 ± 1 pc) |
| Absolute magnitude (MV) | +0.01[8] |
| Details[note 1] | |
| Mass | 4±0.1[9] M☉ |
| Radius | 2.86±1.04[10] R☉ |
| Luminosity | 244+19 −18[3] L☉ |
| Surface gravity (log g) | 3.92/4.20[11] cgs |
| Temperature | 13,934±70[12] K |
| Rotational velocity (v sin i) | 270±24[13] km/s |
| Age | 57±28[9] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
HD 26670, also known as HR 1305, is a star located in the northern circumpolar constellation of Camelopardalis, the giraffe. The object has been designated as 26 H. Camelopardalis, but is not commonly used in modern times. It has an apparent magnitude of 5.70,[2] allowing it to be faintly visible to the naked eye. Based on parallax measurements from Gaia DR3, the object is estimated to be 491 light years away from the Solar System.[1] It appears to be slowly receding with a heliocentric radial velocity of 0.4 km/s.
Characteristics
[edit]This is a solitary,[15] bluish-white hued B-type main-sequence star with a stellar classification of B7 V.[4] It has also been given a class of B5 Vn[5] with the addition of broad or nebulous absorption lines due to rapid rotation. It has 4 times the mass of the Sun and is estimated to be 57 million years old,[9] having completed only a quarter of its main sequence lifetime.[3] HD 26670 has 2.86 times the radius of the Sun[10] and an effective temperature of 13,934 K.[12] When combined, these parameters yield a luminosity 244 times greater than the Sun's from its photosphere.[3] Like most hot stars, HD 26670 spins rapidly, having a projected rotational velocity of 270 km/s.[13] Huang et al. (2010) give it a velocity of 311 km/s, which is 72% of its breakup velocity.[11] As a result, the surface gravity is greater at the poles rather than the equator and it has an oblate shape.[11]
Notes
[edit]- ^ The values for the surface gravity are for the equator and poles respectively
References
[edit]- ^ a b c d e 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.
- ^ a b c Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". VizieR Online Data Catalog. Bibcode:2002yCat.2237....0D.
- ^ a b c d Zorec, J.; Royer, F. (January 2012). "Rotational velocities of A-type stars IV: Evolution of rotational velocities". Astronomy & Astrophysics. 537: A120. arXiv:1201.2052. Bibcode:2012A&A...537A.120Z. doi:10.1051/0004-6361/201117691. eISSN 1432-0746. ISSN 0004-6361. S2CID 55586789.
- ^ a b Hube, Douglas P. (1970). "The radial velocities of 335 late B-type stars". Memoirs of the Royal Astronomical Society. 72: 233. Bibcode:1970MmRAS..72..233H.
- ^ a b Cowley, A. (November 1972). "Spectral classification of the bright B8 stars". The Astronomical Journal. 77: 750. Bibcode:1972AJ.....77..750C. doi:10.1086/111348. ISSN 0004-6256.
- ^ a b Crawford, D. L. (February 1963). "U, B, V, and Hβ Photometry for the Bright B8- and B9-TYPE Stars". The Astrophysical Journal. 137: 530. Bibcode:1963ApJ...137..530C. doi:10.1086/147526. eISSN 1538-4357. ISSN 0004-637X.
- ^ 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.
- ^ 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.
- ^ a b c Tetzlaff, N.; Neuhäuser, R.; Hohle, M. M. (October 12, 2010). "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun". Monthly Notices of the Royal Astronomical Society. 410 (1). Oxford University Press (OUP): 190–200. arXiv:1007.4883. Bibcode:2011MNRAS.410..190T. doi:10.1111/j.1365-2966.2010.17434.x. ISSN 0035-8711.
- ^ a b Stassun, Keivan G.; Oelkers, Ryan J.; Pepper, Joshua; et al. (20 August 2018). "The TESS Input Catalog and Candidate Target List". The Astronomical Journal. 156 (3): 102. arXiv:1706.00495. Bibcode:2018AJ....156..102S. doi:10.3847/1538-3881/aad050. eISSN 1538-3881.
- ^ a b c Huang, Wenjin; Gies, D. R.; McSwain, M. V. (22 September 2010). "A Stellar Rotation Census of B Stars: From ZAMS to TAMS". The Astrophysical Journal. 722 (1): 605–619. arXiv:1008.1761. Bibcode:2010ApJ...722..605H. doi:10.1088/0004-637X/722/1/605. eISSN 1538-4357. ISSN 0004-637X.
- ^ a b 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.
- ^ a b Abt, Helmut A.; Levato, Hugo; Grosso, Monica (July 2002). "Rotational Velocities of B Stars". The Astrophysical Journal. 573 (1): 359–365. Bibcode:2002ApJ...573..359A. doi:10.1086/340590. ISSN 0004-637X.
- ^ Verbunt, F.; van Gent, R. H. (June 2010). "The star catalogue of Hevelius". Astronomy and Astrophysics. 516: A29. Bibcode:2010A&A...516A..29V. doi:10.1051/0004-6361/201014003. eISSN 1432-0746. ISSN 0004-6361.
- ^ 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.
