Beta Coronae Borealis

Beta Coronae Borealis
Location of β Coronae Borealis (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Corona Borealis
Right ascension 15h 27m 49.7308s[1][2]
Declination +29° 06′ 20.530″[1][2]
Apparent magnitude (V) 3.65 to 3.72[3]
Characteristics
Spectral type A9SrEuCr[4] / F2[5]
U−B color index +0.11[6]
B−V color index +0.28[6]
V−R color index 0.2[1]
R−I color index +0.05[6]
Variable type ACV[3] roAp[5]
Astrometry
Radial velocity (Rv)−18.7±0.9[1] km/s
Proper motion (μ) RA: −181.39[1][2] mas/yr
Dec.: 86.84[1][2] mas/yr
Parallax (π)29.17 ± 0.76 mas[7]
Distance112 ± 3 ly
(34.3 ± 0.9 pc)
Orbit[8]
Period (P)10.27±0.14 y
Semi-major axis (a)0.205±0.002
Eccentricity (e)0.524±0.006
Inclination (i)111.1±0.9°
Longitude of the node (Ω)148.2±0.5°
Periastron epoch (T)B1980.506±0.014
Argument of periastron (ω)
(secondary)
181.3±0.7°
Details[5]
A
Mass2.09±0.15 M
Radius2.63±0.09 R
Luminosity25.3±2.9 L
Temperature7,980±180 K
B
Mass1.40±0.10 M
Radius1.56±0.07 R
Luminosity4.5±0.5 L
Surface gravity (log g)cgs
Temperature6,750±230 K
Metallicity [Fe/H]0.28 dex
Age530±100 Myr
Other designations
Nusakan, β CrB, Beta CrB, 3 Coronae Borealis, BD+29°2670, FK5 572, GC 20795, HD 137909, HIP 75695, HR 5747, SAO 83831, WDS 15278+2906
Database references
SIMBADdata

Beta Coronae Borealis (β Coronae Borealis, abbreviated Beta CrB, β CrB) is a binary star in the constellation of Corona Borealis. It appears to the naked eye to be a single star and is the second-brightest star in its constellation with an apparent visual magnitude varying between 3.65 and 3.72. Based on parallax measurements taken during the Hipparcos mission, it is approximately 112 light-years from the Sun.

The two components are designated Beta Coronae Borealis A (officially named Nusakan /ˈnjsəkæn/, the traditional name of the system)[9][10] and B.

  1. ^ a b c d e f "* bet CrB". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved September 8, 2008.
  2. ^ a b c d Astrometric data, mirrored by SIMBAD from the Hipparcos catalogue, pertains to the center of mass of the β Coronae Borealis binary system. See §2.3.4, Volume 1, The Hipparcos and Tycho Catalogues, European Space Agency, 1997, and the entry in the Hipparcos catalogue (CDS ID I/239.)
  3. ^ a b Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1. Bibcode:2009yCat....102025S.
  4. ^ North, P.; Carquillat, J.-M.; Ginestet, N.; Carrier, F.; Udry, S. (1998). "Multiplicity among peculiar a stars". Astronomy and Astrophysics Supplement Series. 130 (2): 223. arXiv:astro-ph/9712025. Bibcode:1998A&AS..130..223N. doi:10.1051/aas:1998365. S2CID 14002166..
  5. ^ a b c Cite error: The named reference bruntt was invoked but never defined (see the help page).
  6. ^ a b c HR 5747, database entry, The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version), D. Hoffleit and W. H. Warren, Jr., CDS ID V/50. Accessed on line September 8, 2008.
  7. ^ van Leeuwen, F. (2007). "Validation of the New Hipparcos Reduction". Astronomy and Astrophysics. 474 (2): 653–64. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600.
  8. ^ Entry 15278+2906, Sixth Catalog of Orbits of Visual Binary Stars Archived 2005-04-24 at the Wayback Machine, United States Naval Observatory. Accessed on line September 9, 2008.
  9. ^ Kunitzsch, Paul; Smart, Tim (2006). A Dictionary of Modern star Names: A Short Guide to 254 Star Names and Their Derivations (2nd rev. ed.). Cambridge, Massachusetts: Sky Pub. ISBN 978-1-931559-44-7.
  10. ^ "Naming Stars". IAU.org. Retrieved 16 December 2017.