Astronomy:HD 96819

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Short description: Star in the constellation Hydra
HD 96819
Observation data
Equinox J2000.0]] (ICRS)
Constellation Hydra[1]
Right ascension  11h 08m 43.99954s[2]
Declination −28° 04′ 50.4127″[3]
Apparent magnitude (V) 5.43[4]
Characteristics
Spectral type A1V[5]
U−B color index +0.06[6]
B−V color index +0.07[6]
Astrometry
Radial velocity (Rv)16.0±7.4[7] km/s
Proper motion (μ) RA: −72.79[3] mas/yr
Dec.: −22.16[3] mas/yr
Parallax (π)17.97 ± 0.53[3] mas
Distance182 ± 5 ly
(56 ± 2 pc)
Absolute magnitude (MV)1.61[4]
Details
HD 96819 A
Mass1.93[8] M
Radius1.80[8] R
Luminosity20.66[5] L
Surface gravity (log g)4.22±0.08[4] cgs
Temperature8,954[5] K
Rotational velocity (v sin i)249[5] km/s
Age9±1[9] Myr
HD 96819 B
Mass0.51[8] M
Radius0.47[8] R
Other designations
NSV 5101, CD−27°7886, HD 96819, HIP 54477, HR 4334, SAO 179577[10]
Database references
SIMBADdata

HD 96819 is a star in the equatorial constellation of Hydra. It was formerly known by its designation 10 Crateris, but that name fell into disuse after constellations were redrawn and the star was no longer in Crater. It is visible to the naked eye as a dim, white-hued star with an apparent visual magnitude of 5.43.[4] Parallax measurements put it at a distance of 182 light years away from the Sun.[2] This is most likely (98.7% chance) a member of the TW Hydrae association.[9]

This is a rapidly rotating A-type main-sequence star that is about double the mass of the Sun. It emits 20.66 times as much energy as the Sun, at an effective temperature of 8,954 K. HD 96819 is currently 31.5% through its life as a main-sequence star: after that it will swell up as a red giant.[5] It is a young star of around nine million years age,[9] and is a suspected variable star.[11] Previously thought to be a single star,[12] in 2022 a companion star was discovered, making HD 96819 a binary star. The companion star has about half the mass of the Sun.[8]

References

  1. Roman, Nancy G. (1987). "Identification of a constellation from a position". Publications of the Astronomical Society of the Pacific 99 (617): 695. doi:10.1086/132034. Bibcode1987PASP...99..695R  Constellation record for this object at VizieR.
  2. 2.0 2.1 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.
  3. 3.0 3.1 3.2 3.3 van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. doi:10.1051/0004-6361:20078357. Bibcode2007A&A...474..653V. 
  4. 4.0 4.1 4.2 4.3 Allende Prieto, C.; Lambert, D. L. (1999). "Fundamental parameters of nearby stars from the comparison with evolutionary calculations: masses, radii and effective temperatures". Astronomy and Astrophysics 352: 555–562. Bibcode1999A&A...352..555A. 
  5. 5.0 5.1 5.2 5.3 5.4 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. Bibcode2012A&A...537A.120Z. 
  6. 6.0 6.1 Johnson, H. L. (1966). "UBVRIJKL Photometry of the Bright Stars". Communications of the Lunar and Planetary Laboratory 4: 99. Bibcode1966CoLPL...4...99J. 
  7. Kharchenko, N. V. (2007). "Astrophysical supplements to the ASCC-2.5: Ia. Radial velocities of ~55000 stars and mean radial velocities of 516 Galactic open clusters and associations". Astronomische Nachrichten 328 (9): 889. doi:10.1002/asna.200710776. Bibcode2007AN....328..889K. 
  8. 8.0 8.1 8.2 8.3 8.4 Waisberg, Idel; Klein, Ygal; Katz, Boaz (2023). "Binarity and beyond in a stars – I. Survey description and first results of VLTI/GRAVITY observations of VAST targets with high Gaia–Hipparcos accelerations". Monthly Notices of the Royal Astronomical Society 521 (4): 5232–5254. doi:10.1093/mnras/stad872. Bibcode2023MNRAS.521.5232W. 
  9. 9.0 9.1 9.2 Gagné, Jonathan et al. (February 2017), "BANYAN. IX. The Initial Mass Function and Planetary-mass Object Space Density of the TW HYA Association", The Astrophysical Journal Supplement Series 228 (2): 51, doi:10.3847/1538-4365/228/2/18, 18, Bibcode2017ApJS..228...18G. 
  10. "HD 96819". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+96819. 
  11. Samus, N. N. et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1 61 (1): 80−88, doi:10.1134/S1063772917010085, Bibcode2017ARep...61...80S. 
  12. 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.