Astronomy:42 Aurigae

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Short description: Star in the constellation Auriga
42 Aurigae
Observation data
Equinox J2000.0]] (ICRS)
Constellation Auriga
Right ascension  06h 17m 34.6465s[1]
Declination +46° 25′ 26.230″[1]
Apparent magnitude (V) 6.53[2]
Characteristics
Spectral type F0 V[3] or A6 Vp(4481 wk)n[4]
B−V color index 0.263±0.003[2]
Astrometry
Radial velocity (Rv)−12.0±1.0[5] km/s
Proper motion (μ) RA: −43.520[1] mas/yr
Dec.: +11.147[1] mas/yr
Parallax (π)13.24 ± 0.38[1] mas
Distance246 ± 7 ly
(76 ± 2 pc)
Absolute magnitude (MV)2.27[2]
Details
Mass1.70±0.02[6] M
Luminosity10.29[2] L
Surface gravity (log g)4.18±0.14[7] cgs
Temperature7,660±260[7] K
Rotational velocity (v sin i)228[6] km/s
Age1.042[7] Gyr
Other designations
42 Aur, BD+46° 1122, HD 43244, HIP 29884, HR 2228, SAO 40999[8]
Database references
SIMBADdata

42 Aurigae is a star in the northern constellation of Auriga. The designation is from the star catalogue of English astronomer John Flamsteed, first published in 1712. It has an apparent visual magnitude of 6.53,[2] which places it just below the visibility limit for normal eyesight under good seeing conditions. It displays an annual parallax shift of 13.24 mas, which yields a distance estimate of around 246 light years. The star is moving closer to the Sun with a radial velocity of −12 km/s.[5] It is a member of the Ursa Major Moving Group of stars that share a common motion through space.[9]

The star was assigned a stellar classification of F0 V by Nancy Roman in 1949,[3] indicating it is an F-type main-sequence star. However, in 1995 Abt and Morrell catalogued it as class A6 Vp(4481 wk)n;[4] a somewhat hotter and more massive A-type main-sequence star that displays spectral peculiarities as well as nebulous lines brought about by rapid rotation. It is around a billion years old[7] with a high rate of spin, showing a projected rotational velocity of 228 km/s.[6] The star has an estimated 1.7[6] times the mass of the Sun and is radiating 10[2] times the Sun's luminosity from its photosphere at an effective temperature of around 7,660 K.[7]

References

  1. 1.0 1.1 1.2 1.3 1.4 Gaia Collaboration et al. (November 2016), "Gaia Data Release 1. Summary of the astrometric, photometric, and survey properties", Astronomy & Astrophysics 595: 23, doi:10.1051/0004-6361/201629512, A2, Bibcode2016A&A...595A...2G. 
  2. 2.0 2.1 2.2 2.3 2.4 2.5 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode2012AstL...38..331A. 
  3. 3.0 3.1 Roman, Nancy Grace (September 1949), "The Ursa Major Group", Astrophysical Journal 110: 205, doi:10.1086/145199, Bibcode1949ApJ...110..205R. 
  4. 4.0 4.1 Abt, Helmut A.; Morrell, Nidia I. (1995), "The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars", Astrophysical Journal Supplement 99: 135, doi:10.1086/192182, Bibcode1995ApJS...99..135A. 
  5. 5.0 5.1 de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics 546: 14, doi:10.1051/0004-6361/201219219, A61, Bibcode2012A&A...546A..61D. 
  6. 6.0 6.1 6.2 6.3 Zorec, J.; Royer, F. (2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy & Astrophysics 537: A120, doi:10.1051/0004-6361/201117691, A120, Bibcode2012A&A...537A.120Z. 
  7. 7.0 7.1 7.2 7.3 7.4 David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal 804 (2): 146, doi:10.1088/0004-637X/804/2/146, Bibcode2015ApJ...804..146D. 
  8. "42 Aur". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=42+Aur. 
  9. Chupina, N. V. et al. (June 2006), "Kinematic structure of the corona of the Ursa Major flow found using proper motions and radial velocities of single stars", Astronomy and Astrophysics 451 (3): 909–916, doi:10.1051/0004-6361:20054009, Bibcode2006A&A...451..909C.