87 Leonis is a single[7] star in the zodiac constellation of Leo,[6] located approximately 480[1] light years away from the Sun. It has the Bayer designation e Leonis; 87 Leonis is the Flamsteed designation. This object is visible by the naked eye as a faint orange-hued star with an apparent visual magnitude of 4.77.[2] It is moving away from the Earth with a heliocentric radial velocity of 19 km/s.[2] The star is positioned near the ecliptic and thus is subject to occultation by the Moon.[8]
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Leo |
| Right ascension | 11h 30m 18.89196s[1] |
| Declination | −03° 00′ 12.5712″[1] |
| Apparent magnitude (V) | 4.77[2] |
| Characteristics | |
| Spectral type | K3+ III Fe−0.5[3] |
| U−B color index | +1.529±0.016[2] |
| B−V color index | +1.54[4] |
| R−I color index | +0.84[4] |
| Astrometry | |
| Radial velocity (Rv) | 18.8±0.8[2] km/s |
| Proper motion (μ) | RA: 20.901[1] mas/yr Dec.: −17.944[1] mas/yr |
| Parallax (π) | 6.7249 ± 0.2901 mas[1] |
| Distance | 480 ± 20 ly (149 ± 6 pc) |
| Absolute magnitude (MV) | −1.56[2] |
| Details | |
| Radius | 54[1] R☉ |
| Luminosity | 641[1] L☉ |
| Surface gravity (log g) | 1.56±0.20[5] cgs |
| Temperature | 4,001±32[5] K |
| Metallicity [Fe/H] | −0.24±0.07[5] dex |
| Rotational velocity (v sin i) | ≤ 19[4] km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is an aging K-type giant star with a stellar classification of K3+ III Fe−0.5,[3] which means it has exhausted the hydrogen at its core and evolved away from the main sequence. The suffix notation indicates a mild underabundance of iron in the atmosphere. It has expanded to 37[9] times the Sun's radius and is radiating over a thousand[2] times the Sun's luminosity from its photosphere at an effective temperature of 4,001 K.[5]
References
edit- ^ a b c d e f g h Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b c d e f g Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
- ^ 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 Hoffleit, Dorrit; Jaschek, Carlos (1991), "HR 4432", The Bright star catalogue (5th Revised ed.), New Haven, Conn.: Yale University Observatory, Bibcode:1991bsc..book.....H, retrieved 2010-11-08.
- ^ a b c d Prugniel, Ph.; et al. (July 2011), "The atmospheric parameters and spectral interpolator for the MILES stars", Astronomy & Astrophysics, 531: A165, arXiv:1104.4952, Bibcode:2011A&A...531A.165P, doi:10.1051/0004-6361/201116769, S2CID 54940439.
- ^ a b "87 Leo". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-02-09.
- ^ Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society, 389 (2): 869–879, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
- ^ Dunham, D. W.; Evans, D. S.; et al. (April 1974), "The angular diameter of 87 Leonis.", Astronomical Journal, 79: 483–484, Bibcode:1974AJ.....79..483D, doi:10.1086/111568
- ^ Pasinetti Fracassini, L. E.; Pastori, L.; Covino, S.; Pozzi, A. (February 2001). "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)". Astronomy and Astrophysics. 367 (Third ed.): 521–524. arXiv:astro-ph/0012289. Bibcode:2001A&A...367..521P. doi:10.1051/0004-6361:20000451. S2CID 425754.