Astronomy:Omicron Boötis
| Observation data 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[1] mas/yr Dec.: −52.524[1] mas/yr |
| Parallax (π) | 12.6814 ± 0.1385[1] mas |
| 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 | |
| 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
- ↑ 1.0 1.1 1.2 1.3 1.4 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940. Gaia DR3 record for this source at VizieR.
- ↑ 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 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.
- ↑ 4.0 4.1 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.
- ↑ 5.0 5.1 5.2 5.3 5.4 5.5 5.6 5.7 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.
- ↑ 7.0 7.1 7.2 7.3 7.4 7.5 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.
- ↑ 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.
