Omicron Boötis
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Boötes |
| Right ascension | 14h 45m 14.461s[1] |
| Declination | +16° 57′ 51.40″[1] |
| Apparent magnitude (V) | +4.60[2] |
| Characteristics | |
| Evolutionary stage | red clump[3] |
| Spectral type | G8.5 III[4] |
| U−B color index | +0.75[2] |
| B−V color index | +0.98[2] |
| Astrometry | |
| Radial velocity (Rv) | −9.18[5] km/s |
| Proper motion (μ) | RA: −59.581 mas/yr[1] Dec.: −52.524 mas/yr[1] |
| Parallax (π) | 12.6814±0.1385 mas[1] |
| Distance | 257 ± 3 ly (78.9 ± 0.9 pc) |
| Absolute magnitude (MV) | 0.70[6] |
| Details | |
| Mass | 2.05[5] M☉ |
| Radius | 11[7] R☉ |
| Luminosity | 85[5] L☉ |
| Surface gravity (log g) | 2.7[7] cgs |
| Temperature | 4,864±25[5] K |
| Metallicity [Fe/H] | −0.10[7] dex |
| Rotational velocity (v sin i) | 3.6[7] km/s |
| Age | 2.72[5] Gyr |
| Other designations | |
| ο Boo, 35 Boötis, BD+17°2780, GC 19858, GJ 9493, HD 129972, HIP 72125, HR 5502, SAO 101184[8] | |
| Database references | |
| SIMBAD | data |
Omicron Boötis is a yellow-hued star in the northern constellation of Boötes. Its name is a Bayer designation that is Latinized from ο Boötis, and abbreviated Omicron Boo or ο Boo. With an apparent visual magnitude of +4.60,[2] it is a fifth magnitude star that is faintly visible to the naked eye. Based upon an annual parallax shift of 12.68 mas as seen from the Earth,[1] it is located at a distance of approximately 257 light-years (78.9 pc). The star is moving closer to the Sun with a radial velocity of −9 km/s.[7]
At the age of 2.72 billion years,[5] this is an evolved G-type giant star with a stellar classification of G8.5 III.[4] It belongs to the so-called red clump, which indicates it is generating energy through helium fusion at its core.[3] 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[5] the mass of the Sun and has expanded to 11[7] 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.[5]
References
[edit]- ^ a b c d e Vallenari, A.; et al. (Gaia collaboration) (2023), "Gaia Data Release 3. Summary of the content and survey properties", Astronomy and Astrophysics, 674: A1, arXiv:2208.00211, Bibcode:2023A&A...674A...1G, doi:10.1051/0004-6361/202243940, S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ a b c d 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.
- ^ a b Alves, David R. (August 2000), "K-Band Calibration of the Red Clump Luminosity", The Astrophysical Journal, 539 (2): 732–741, arXiv:astro-ph/0003329, Bibcode:2000ApJ...539..732A, doi:10.1086/309278, S2CID 16673121.
- ^ a b Keenan, Philip C.; McNeil, Raymond C. (1989), "The Perkins catalog of revised MK types for the cooler stars", Astrophysical Journal Supplement Series, 71: 245, Bibcode:1989ApJS...71..245K, doi:10.1086/191373.
- ^ a b c d e f g h Luck, R. Earle (September 2015), "Abundances in the Local Region. I. G and K Giants", The Astronomical Journal, 150 (3): 23, arXiv:1507.01466, Bibcode:2015AJ....150...88L, doi:10.1088/0004-6256/150/3/88, S2CID 118505114, 88.
- ^ 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, Bibcode:1990ApJS...74.1075M, doi:10.1086/191527.
- ^ a b c d e f 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, Bibcode:2008AJ....135..209M, doi:10.1088/0004-6256/135/1/209, S2CID 121883397.
- ^ "omi Boo", SIMBAD, Centre de données astronomiques de Strasbourg, retrieved 2017-09-09.
- ^ 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, Bibcode:1975MNRAS.170..343W, doi:10.1093/mnras/170.2.343.
External links
[edit]- Hoffleit; et al. (1991), "HR 5502", Bright Star Catalogue (5th Revised ed.), retrieved 2017-09-12.
- "omi Boo", Aladin previewer, Centre de Données astronomiques de Strasbourg, retrieved 2017-09-12.
