Astronomy:HD 93905

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Short description: Star in the constellation Antlia
HD 93905
Antlia constellation map.svg
Red circle.svg
Location of HD 93905 (circled)
Observation data
Equinox J2000.0]] (ICRS)
Constellation Antlia
Right ascension  10h 49m 57.0188s[1]
Declination −34° 03′ 29.4506″[1]
Apparent magnitude (V) 5.61[2]
Characteristics
Evolutionary stage main sequence[3]
Spectral type A1 V[4]
U−B color index +0.05[5]
B−V color index +0.04[5]
Astrometry
Radial velocity (Rv)−9.5±1.3[6] km/s
Proper motion (μ) RA: −41.069[1] mas/yr
Dec.: +5.845[1] mas/yr
Parallax (π)8.7989 ± 0.1617[1] mas
Distance371 ± 7 ly
(114 ± 2 pc)
Absolute magnitude (MV)0.00[2]
Details[3]
Mass2.78±0.05 M
Radius3.89[7] R
Luminosity101±9 L
Surface gravity (log g)3.77[8] cgs
Temperature8995+125
−123
 K
Rotational velocity (v sin i)85[9] km/s
Age256±6 Myr
Other designations
Database references
SIMBADdata

HD 93905 (HR 4238) is a solitary star located in the southern constellation Antlia. The star has an absolute magnitude of 0[2] and an apparent magnitude of 5.61,[2] making it faintly visible to the naked eye under ideal conditions. The star is located 371 light years[1] away based on its parallax shift and is drifting closer with a helocentric radial velocity of −9.6 km/s.[6]

This star has a classification of A1 V,[4] which indicates that it is an ordinary A-type main-sequence star that is fusing hydrogen at its core. At present it has 2.78[3] times the mass of the Sun but is large and over luminous for its class with 3.89[7] times and 101[3] times the radius and luminosity of the Sun respectively. This is because HD 93905 has already completed most of its main sequence lifetime at an age of 256 million years.[3] HD 93905 has a surface temperature of 8,895 K[3] and spins quickly with a projected rotational velocity of 85 km/s.[9]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  2. 2.0 2.1 2.2 2.3 Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331–346. doi:10.1134/S1063773712050015. ISSN 1063-7737. Bibcode2012AstL...38..331A. 
  3. 3.0 3.1 3.2 3.3 3.4 3.5 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. Bibcode2012A&A...537A.120Z. 
  4. 4.0 4.1 Houk, N. (1982). Michigan Catalogue of Two-dimensional Spectral Types for the HD stars. Volume_3. Declinations -40_ƒ0 to -26_ƒ0.. Bibcode1982mcts.book.....H. 
  5. 5.0 5.1 Johnson, H. L.; Mitchell, R. I.; Iriarte, B.; Wisniewski, W. Z. (1966). "UBVRIJKL Photometry of the Bright Stars". Communications of the Lunar and Planetary Laboratory 4: 99–110. Bibcode1966CoLPL...4...99J. 
  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. Bibcode2006AstL...32..759G. 
  7. 7.0 7.1 McDonald, I.; Zijlstra, A. A.; Watson, R. A. (11 October 2017). "Fundamental parameters and infrared excesses of Tycho–Gaia stars". Monthly Notices of the Royal Astronomical Society 471 (1): 770–791. doi:10.1093/mnras/stx1433. ISSN 0035-8711. Bibcode2017MNRAS.471..770M. 
  8. 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. Bibcode2019A&A...628A..94A. 
  9. 9.0 9.1 Royer, F.; Zorec, J.; Gómez, A. E. (February 2007). "Rotational velocities of A-type stars: III. Velocity distributions". Astronomy & Astrophysics 463 (2): 671–682. doi:10.1051/0004-6361:20065224. ISSN 0004-6361. Bibcode2007A&A...463..671R.