Beta Equulei

Beta Equulei
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Equuleus
Right ascension 21h 22m 53.61365s[1]
Declination +06° 48′ 40.1125″[1]
Apparent magnitude (V) 5.16[2]
Characteristics
Evolutionary stage Main sequence[3]
Spectral type A3 V[4]
U−B color index +0.10[5]
B−V color index +0.064±0.003[2]
Astrometry
Radial velocity (Rv)−11.1±0.8[6] km/s
Proper motion (μ) RA: +53.685[1] mas/yr
Dec.: +10.136[1] mas/yr
Parallax (π)11.2696 ± 0.2608 mas[1]
Distance289 ± 7 ly
(89 ± 2 pc)
Absolute magnitude (MV)+0.13[2]
Details
Mass2.74±0.04[3] M☉
Radius4.02[7] R☉
Luminosity78.3[2] L☉
Temperature9,000[7] K
Rotational velocity (v sin i)58.0±0.7[4] km/s
Age600[7] Myr
Other designations
β Equ, 10 Equulei, BD+06°4811, HD 203562, HIP 105570, HR 8178, SAO 126749, WDS 21229+0649A[8]
Database references
SIMBADdata

Beta Equulei, Latinized from β Equulei, is the Bayer designation for a solitary[9] star in the northern constellation of Equuleus. It is faintly visible to the naked eye with an apparent visual magnitude of 5.16.[2] The annual parallax shift is 11.27 mas,[1] indicating a separation of around 289 light years from the Sun. It is drifting closer with a radial velocity of −11 km/s.[6]

This is an ordinary A-type main sequence star with a stellar classification of A3 V.[4] It has 2.7 times the mass of the Sun[3] and about four[7] times the Sun's radius. The star is around 600[7] million years old – 93%[3] of the way through its main sequence lifetime – and is spinning with a projected rotational velocity of 58 km/s.[4] It is radiating 78[2] times the luminosity of the Sun from its photosphere at an effective temperature of about 9,000 K.[7] The star emits an infrared excess indicating the presence of a dusty debris disk. The mean temperature of the dust is 85 K, indicating the semimajor axis of its orbit is 104 AU.[7]

β Equulei has four optical companions. They are not physically associated with the star described above.[10]

  1. ^ a b c d e f Cite error: The named reference GaiaDR2 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 Cite error: The named reference Zorec_Royer_2012 was invoked but never defined (see the help page).
  4. ^ a b c d Cite error: The named reference Diaz2011 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference Mermilliod1986 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Gontcharov2006 was invoked but never defined (see the help page).
  7. ^ a b c d e f g Cite error: The named reference Rhee2007 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).
  10. ^ Cite error: The named reference WDSC2014 was invoked but never defined (see the help page).