Astronomy:HD 31134

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Short description: Star in the constellation of Camelopardalis
HD 31134
Location of HD 31134 on the map (circled)
Observation data
Epoch J2000.0   Equinox (celestial coordinates)
Constellation Camelopardalis
Right ascension  04h 56m 07.07238s[1]
Declination +52° 52′ 11.0544″[1]
Apparent magnitude (V) 5.74±0.01[2]
Characteristics
Evolutionary stage main sequence star[3]
Spectral type A2 Vs[4] or A1 Vp[5]
U−B color index +0.11[2]
B−V color index +0.09[2]
Astrometry
Radial velocity (Rv)−15.1±2.5[6] km/s
Proper motion (μ) RA: −3.418[1] mas/yr
Dec.: +14.954[1] mas/yr
Parallax (π)6.8897 ± 0.1144[1] mas
Distance473 ± 8 ly
(145 ± 2 pc)
Absolute magnitude (MV)+0.19[7]
Details
Mass2.74±0.05[3] M☉
Radius4.38±0.22[8] R☉
Luminosity103+13−11[3] L☉
Surface gravity (log g)3.85[9] cgs
Temperature8,690[9] K
Metallicity [Fe/H]−0.11[10] dex
Rotational velocity (v sin i)60±1[11] km/s
Age432[12] Myr
Other designations
BD+52°898, GC 5988, HD 31134, HIP 22936, HR 1561, SAO 24919[13]
Database references
SIMBADdata

HD 31134, also designated as HR 1561, is a solitary star[14] located in the northern circumpolar constellation Camelopardalis, the giraffe. It is faintly visible to the naked eye as a white-hued star with an apparent magnitude of 5.74.[2] Gaia DR3 parallax measurements place it 473 light years away.[1] It appears to be approaching the Solar System with a heliocentric radial velocity of −15.1 km/s.[6] At its current distance, HD 31134's brightness is diminished by 0.35 magnitudes due to interstellar dust.[15] It has an absolute magnitude of +0.19.[7]

The object has a stellar classification of A2 Vs,[4] indicating that it is an A-type main-sequence star with sharp or narrow absorption lines due to slow rotation. Two sources remove the s prefix and instead list it as an ordinary dwarf star[16][17] while one lists it as a more evolved giant star.[18] Abt and Morell (1995) list it as a slightly hotter peculiar Ap star,[5] but it is now considered unlikely to be chemically peculiar.[19] It has 2.74 times the mass of the Sun and an enlarged radius of 4.38 R☉.[8] It radiates 103 times the luminosity of the Sun[3] from its photosphere at an effective temperature of 8,690 K.[9] HD 31134 is a rather evolved star, having completed 97.6% of its main sequence lifetime[3] at the age of 432 million years.[12] Consistent with its spectrum, it spins modestly with a projected rotational velocity of 60 km/s.[11]

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 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. ↑ 2.0 2.1 2.2 2.3 Oja, T. (August 1991). "UBV photometry of stars whose positions are accurately known. VI.". Astronomy and Astrophysics Supplement Series 89: 415. ISSN 0365-0138. Bibcode: 1991A&AS...89..415O. 
  3. ↑ 3.0 3.1 3.2 3.3 3.4 Zorec, J.; Royer, F. (January 2012). "Rotational velocities of A-type stars IV: Evolution of rotational velocities". Astronomy & Astrophysics 537: A120. doi:10.1051/0004-6361/201117691. ISSN 0004-6361. Bibcode: 2012A&A...537A.120Z. 
  4. ↑ 4.0 4.1 Cowley, A.; Cowley, C.; Jaschek, M.; Jaschek, C. (April 1969). "A study of the bright stars. I. A catalogue of spectral classifications.". The Astronomical Journal 74: 375. doi:10.1086/110819. ISSN 0004-6256. Bibcode: 1969AJ.....74..375C. 
  5. ↑ 5.0 5.1 Abt, Helmut A.; Morrell, Nidia I. (July 1995). "The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars". The Astrophysical Journal Supplement Series 99: 135. doi:10.1086/192182. ISSN 0067-0049. Bibcode: 1995ApJS...99..135A. 
  6. ↑ 6.0 6.1 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. 
  7. ↑ 7.0 7.1 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. 
  8. ↑ 8.0 8.1 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. 
  9. ↑ 9.0 9.1 9.2 Philip, A. G. D.; Egret, D. (May 1980). "An analysis of the Hauck-Mermillod catalogue of homogeneous four-color data. II.". Astronomy and Astrophysics Supplement Series 40: 199–205. ISSN 0365-0138. Bibcode: 1980A&AS...40..199P. 
  10. ↑ 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. doi:10.1051/0004-6361/201935765. ISSN 0004-6361. Bibcode: 2019A&A...628A..94A. 
  11. ↑ 11.0 11.1 Royer, F.; Grenier, S.; Baylac, M.-O.; Gómez, A. E.; Zorec, J. (October 2002). "Rotational velocities of A-type stars in the northern hemisphere. II. Measurement of v sin i". Astronomy & Astrophysics 393 (3): 897–911. doi:10.1051/0004-6361:20020943. ISSN 0004-6361. Bibcode: 2002A&A...393..897R. 
  12. ↑ 12.0 12.1 Gontcharov, G. A. (December 2012). "Dependence of kinematics on the age of stars in the solar neighborhood". Astronomy Letters 38 (12): 771–782. doi:10.1134/S1063773712120031. ISSN 1063-7737. Bibcode: 2012AstL...38..771G. 
  13. ↑ "HR 1561". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HR+1561. 
  14. ↑ 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. 
  15. ↑ 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. 
  16. ↑ 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. 
  17. ↑ Cucchiaro, A.; Macau-Hercot, D.; Jaschek, M.; Jaschek, C. (July 1978). "Spectral classification from the ultraviolet line features of S2/68 spectra. III. Early A-type stars.". Astronomy and Astrophysics Supplement Series 33: 15–26. ISSN 0365-0138. Bibcode: 1978A&AS...33...15C. 
  18. ↑ Palmer, D. R.; Walker, E. N.; Jones, D. H. P.; Wallis, R. E. (1968). "The radial velocities spectral types and projected rotational velocities of 633 bright northern A stars.". Royal Greenwich Observatory Bulletins 135: 385. Bibcode: 1968RGOB..135..385P. 
  19. ↑ Renson, P.; Manfroid, J. (19 March 2009). "Catalogue of Ap, HgMn and Am stars". Astronomy & Astrophysics 498 (3): 961–966. doi:10.1051/0004-6361/200810788. ISSN 0004-6361. Bibcode: 2009A&A...498..961R.