Beta Ophiuchi

Beta Ophiuchi
Location of β Ophiuchi (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Ophiuchus
Right ascension 17h 43m 28.35191s[1]
Declination +04° 34′ 02.2932″[1]
Apparent magnitude (V) 2.749[2] (2.75 to 2.77)[citation needed]
Characteristics
Spectral type K2 III[3]
U−B color index +1.253[2]
B−V color index +1.170[2]
Astrometry
Radial velocity (Rv)–12.53[4] km/s
Proper motion (μ) RA: −41.793 mas/yr[1]
Dec.: 150.43 mas/yr[1]
Parallax (π)39.2284 ± 0.2027 mas[1]
Distance83.1 ± 0.4 ly
(25.5 ± 0.1 pc)
Absolute magnitude (MV)+0.77 ± 0.04[5]
Details[6]
Mass1.44±0.16[6] – 1.75±0.174[7] M☉
Radius12.17±0.06 R☉
Luminosity57.7±2.9 L☉
Surface gravity (log g)2.33±0.07[7] cgs
Temperature4,559±67 K
Metallicity [Fe/H]0.06±0.04[7] dex
Rotational velocity (v sin i)5.4[8] km/s
Age2.75±0.78 Gyr
Other designations
Cebalrai, Celbalrai, Cheleb[9], Kelb Alrai, Bet Oph, β Oph, β Ophiuchi, 60 Oph, 60 Ophiuchi, BD+04°3489, FK5 665, HD 161096, HIP 86742, HR 6603, SAO 122671[10]
Database references
SIMBADdata

Beta Ophiuchi or β Ophiuchi, also named Cebalrai /ˌsɛbəlˈreɪ.iː/,[11][12] is a star in the equatorial constellation of Ophiuchus. The apparent visual magnitude of this star is 2.7,[2] which is readily visible to the naked eye even from urban skies. The distance to this star can be estimated using parallax measurements, yielding a value of 83.4 light-years (25.6 parsecs) from the Sun.[1]

  1. ^ a b c d e Cite error: The named reference DR3 was invoked but never defined (see the help page).
  2. ^ a b c d Cite error: The named reference aaass65_2_405 was invoked but never defined (see the help page).
  3. ^ Cite error: The named reference aaa480_1_91 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference aaa430_165 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference aj135_3_892 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Baines2018 was invoked but never defined (see the help page).
  7. ^ a b c Cite error: The named reference Soubiran2024 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference aj135_1_209 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference allen1899 was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  11. ^ Davis, George A. (1944). "The pronunciations, derivations, and meanings of a selected list of star names". Popular Astronomy. 52: 8–30. Bibcode:1944PA.....52....8D.
  12. ^ "IAU Catalog of Star Names". Retrieved 28 July 2016.