Astronomy:HD 56405

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Short description: Star in the constellation Canis Major
HD 56405
Canis Major constellation map.svg
Red circle.svg
Location of HD 56405 (circled)
Observation data
Equinox J2000.0]] (ICRS)
Constellation Canis Major
Right ascension  07h 16m 14.55342s[1]
Declination −15° 35′ 08.4724″
Apparent magnitude (V) 5.45[2]
Characteristics
Spectral type A1V[3]
B−V color index 0.079±0.005[4]
Astrometry
Radial velocity (Rv)+6.30±0.9[5] km/s
Proper motion (μ) RA: -46.118[1] mas/yr
Dec.: -15.488[1] mas/yr
Parallax (π)13.1152 ± 0.1293[1] mas
Distance249 ± 2 ly
(76.2 ± 0.8 pc)
Absolute magnitude (MV)0.88[4]
Details
Mass2.13[6] M
Luminosity38.86[4] L
Surface gravity (log g)4.14±0.14[6] cgs
Temperature9,562±325[6] K
Rotational velocity (v sin i)149[6] km/s
Age212[6] Myr
Other designations
BD−15°1734, FK5 2561, GC 9657, GJ 9228, HD 56405, HIP 35180, HR 2758, SAO 152641, TYC 5965-363-1[7]
Database references
SIMBADdata

HD 56405 is a star in the southern constellation of Canis Major. It is white in hue and is dimly visible to the naked eye with an apparent visual magnitude of 5.45.[2] To the east of HD 56405 is the open cluster NGC 2360, also known as Caroline's Cluster.[8] The distance to HD 56405, as determined from parallax measurements, is approximately 249 light years. It is drifting further away with a radial velocity (RV) of about +6 km/s.[5] Although classed as a single star,[9] it is to suspected to vary in RV.[10]

This is an A-type main-sequence star with a stellar classification of A1V.[3] It was classed as a candidate Lambda Boötis star,[11] but as of 2015 this classification has been rejected by astronomers due to the star having an inconsistent UV flux, possible RV variability, and a fairly high rotation rate.[2] The star is about 212 million years old with 2.13 times the mass of the Sun and is spinning with a projected rotational velocity of 149 km/s.[6] It is radiating 39[4] times the luminosity of the Sun from its photosphere at an effective temperature of around 9,562 K.[6]

References

  1. 1.0 1.1 1.2 1.3 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 Murphy, Simon J. et al. (October 2015). "An Evaluation of the Membership Probability of 212 λ Boo Stars. I. A Catalogue". Publications of the Astronomical Society of Australia 32: 43. doi:10.1017/pasa.2015.34. e036. Bibcode2015PASA...32...36M. 
  3. 3.0 3.1 Houk, Nancy; Smith-Moore, M. (1978). Michigan catalogue of two-dimensional spectral types for the HD stars. 4. Ann Arbor: Dept. of Astronomy, University of Michigan. Bibcode1988mcts.book.....H. 
  4. 4.0 4.1 4.2 4.3 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode2012AstL...38..331A. 
  5. 5.0 5.1 Gontcharov, G. A. (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. Bibcode2006AstL...32..759G. 
  6. 6.0 6.1 6.2 6.3 6.4 6.5 6.6 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. 
  7. "HD 56405". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+56405. 
  8. Streicher, M. (December 2005). "Deepsky Delights: Caroline Herschel's deepsky discoveries". Monthly Notes of the Astronomical Society of Southern Africa 64 (11 and 12): 234–236. Bibcode2005MNSSA..64..234S. 
  9. Eggleton, P. P.; Tokovinin, A. A. (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. Bibcode2008MNRAS.389..869E. 
  10. Gerbaldi, M. et al. (December 2003). "The heterogeneous class of lambda Bootis stars". Astronomy and Astrophysics 412 (2): 447–464. doi:10.1051/0004-6361:20031472. Bibcode2003A&A...412..447G. 
  11. Renson, P. et al. (December 1990). "Catalogue of Lambda Bootis Candidates". Bulletin d'Information du Centre de Données Stellaires 38: 137. Bibcode1990BICDS..38..137R.