HD 57821

HD 57821
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Canis Major
Right ascension 07h 22m 13.52901s[1]
Declination −19° 00′ 59.7646″[1]
Apparent magnitude (V) 4.94[2]
Characteristics
Evolutionary stage Main sequence[3]
Spectral type B5 II/III[4] or B7 IV[5]
B−V color index −0.039±0.024[2]
Astrometry
Radial velocity (Rv)+32.9±1.6[2] km/s
Proper motion (μ) RA: −1.69[1] mas/yr
Dec.: +6.91[1] mas/yr
Parallax (π)6.78 ± 0.26 mas[1]
Distance480 ± 20 ly
(147 ± 6 pc)
Absolute magnitude (MV)−0.90[2]
Details
Mass4.12±0.08[3] M☉
Radius4.7[6] R☉
Luminosity489+43
−40[3] L☉
Temperature12,445±86[3] K
Rotational velocity (v sin i)116[3] km/s
Age291[7] Myr
Other designations
BD−18°1806, FK5 2570, HD 57821, HIP 35727, HR 2812, SAO 152776[8]
Database references
SIMBADdata

HD 57821 is a single[9] star in the southern constellation of Canis Major. It has a blue-white hue and is faintly visible to the naked eye with an apparent visual magnitude of 4.94.[2] Based on parallax measurements, the distance to this object is approximately 480 light years. It is drifting further away with a radial velocity of +33 km/s, having come to within 71 light-years some 4.3 million years ago.[2]

The stellar classification of this star is B5 II/III,[4] which matches the spectrum of a giant/bright giant although stellar models suggest it may still be on the main sequence.[3] It has over four[3] times the mass of the Sun and is 291[7] million years old. The star has a high rate of spin, showing a projected rotational velocity of 116 km/s.[3] It is radiating around 489[3] times the luminosity of the Sun from its photosphere at an effective temperature of 12,445 K.[3]

  1. ^ a b c d e Cite error: The named reference vanLeeuwen2007 was invoked but never defined (see the help page).
  2. ^ a b c d e f Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  3. ^ a b c d e f g h i j Cite error: The named reference Zorec2012 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference houk1978 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference Cowley1972 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Fracassini2001 was invoked but never defined (see the help page).
  7. ^ a b Cite error: The named reference Gontcharov2012 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).