Astronomy:Omicron Boötis
Observation data Equinox J2000.0]] (ICRS) | |
---|---|
Constellation | Boötes |
Right ascension | 14h 45m 14.46026s[1] |
Declination | +16° 57′ 51.4078″[1] |
Apparent magnitude (V) | +4.60[2] |
Characteristics | |
Spectral type | G8.5 III[3] |
U−B color index | +0.75[2] |
B−V color index | +0.98[2] |
Astrometry | |
Radial velocity (Rv) | −9.18[4] km/s |
Proper motion (μ) | RA: −60.69[1] mas/yr Dec.: −50.56[1] mas/yr |
Parallax (π) | 13.42 ± 0.24[1] mas |
Distance | 243 ± 4 ly (75 ± 1 pc) |
Absolute magnitude (MV) | 0.70[5] |
Details | |
Mass | 2.05[4] M☉ |
Radius | 11[6] R☉ |
Luminosity | 85[4] L☉ |
Surface gravity (log g) | 2.7[6] cgs |
Temperature | 4,864±25[4] K |
Metallicity [Fe/H] | −0.10[6] dex |
Rotational velocity (v sin i) | 3.6[6] km/s |
Age | 2.72[4] Gyr |
Other designations | |
Database references | |
SIMBAD | data |
Omicron Boötis (ο Boötis) is a yellow-hued star in the northern constellation of Boötes. With an apparent visual magnitude of +4.60,[2] it is a fifth magnitude star that is visible to the naked eye. Based upon an annual parallax shift of 13.42 mas as seen from the Earth,[1] it is located about 243 light years from the Sun. The star is moving closer to the Sun with a radial velocity of −9 km/s.[6]
At the age of 2.72 billion years,[4] this is an evolved G-type giant star with a stellar classification of G8.5 III.[3] It belongs to the so-called "red clump", which indicates it is generating energy through helium fusion at its core.[8] Although it displays a higher abundance of barium than is normal for a star of its type, Williams (1975) considers its status as a Barium star to be "very doubtful".[9] The star has double[4] the mass of the Sun and has expanded to 11[6] times the Sun's radius. It is radiating 85 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,864 K.[4]
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, doi:10.1051/0004-6361:20078357, Bibcode: 2007A&A...474..653V.
- ↑ 2.0 2.1 2.2 2.3 Johnson, H. L. et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory 4 (99): 99, Bibcode: 1966CoLPL...4...99J.
- ↑ 3.0 3.1 Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins catalog of revised MK types for the cooler stars", Astrophysical Journal Supplement Series 71: 245, doi:10.1086/191373, Bibcode: 1989ApJS...71..245K.
- ↑ 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7 Luck, R. Earle (September 2015), "Abundances in the Local Region. I. G and K Giants", The Astronomical Journal 150 (3): 23, doi:10.1088/0004-6256/150/3/88, 88, Bibcode: 2015AJ....150...88L.
- ↑ McWilliam, Andrew (December 1990), "High-resolution spectroscopic survey of 671 GK giants. I - Stellar atmosphere parameters and abundances", Astrophysical Journal Supplement Series 74: 1075–1128, doi:10.1086/191527, Bibcode: 1990ApJS...74.1075M.
- ↑ 6.0 6.1 6.2 6.3 6.4 6.5 Massarotti, Alessandro et al. (January 2008), "Rotational and radial velocities for a sample of 761 HIPPARCOS giants and the role of binarity", The Astronomical Journal 135 (1): 209–231, doi:10.1088/0004-6256/135/1/209, Bibcode: 2008AJ....135..209M.
- ↑ "omi Boo". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=omi+Boo.
- ↑ Alves, David R. (August 2000), "K-Band Calibration of the Red Clump Luminosity", The Astrophysical Journal 539 (2): 732–741, doi:10.1086/309278, Bibcode: 2000ApJ...539..732A.
- ↑ Williams, P. M. (February 1975), "Stellar compositions from narrow-band photometry - V. Barium abundances for 200 evolved stars", Monthly Notices of the Royal Astronomical Society 170 (2): 343–362, doi:10.1093/mnras/170.2.343, Bibcode: 1975MNRAS.170..343W.
External links
- Hoffleit (1991), "HR 5502", Bright Star Catalogue, http://webviz.u-strasbg.fr/viz-bin/VizieR-S?HR%205502, retrieved 2017-09-12.
- "omi Boo", Aladin previewer (Centre de Données astronomiques de Strasbourg), http://aladin.u-strasbg.fr/AladinPreview?-c=14+45+14.4601%2B16+57+51.407&ident=*+omi+Boo&submit=Aladin+previewer, retrieved 2017-09-12.
Original source: https://en.wikipedia.org/wiki/Omicron Boötis.
Read more |