Eta Leonis
 
| |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Leo |
| Right ascension | 10h 07m 19.95186s[1] |
| Declination | 16° 45′ 45.592″[1] |
| Apparent magnitude (V) | 3.486[2] |
| Characteristics | |
| Spectral type | A0 Ib[2] |
| U−B color index | −-0.206[2] |
| B−V color index | −0.026[2] |
| Astrometry | |
| Radial velocity (Rv) | 1.40[3] km/s |
| Proper motion (μ) | RA: −2.80[1] mas/yr Dec.: −1.82[1] mas/yr |
| Parallax (π) | 2.57 ± 0.16[1] mas |
| Distance | 1,270 ± 80 ly (390 ± 20 pc) |
| Absolute magnitude (MV) | -5.54[4] |
| Details | |
| Mass | 10[5] M☉ |
| Radius | 47[4] R☉ |
| Luminosity | 19,000[5] L☉ |
| Surface gravity (log g) | 2.00[5] cgs |
| Temperature | 9,600[2] K |
| Metallicity | -0.04[4] |
| Rotational velocity (v sin i) | 2[2] km/s |
| Age | 25[5] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Eta Leonis (η Leo, η Leonis) is a fourth-magnitude star in the constellation Leo. It doesn't have a proper name. Since 1943, the spectrum of this star has served as one of the stable anchor points by which other stars are classified.[6]
Properties
Eta Leonis is a white supergiant with the stellar classification A0Ib. Though its apparent magnitude is 3.5, making it a relatively dim star to the naked eye, it is nearly 20,000 times more luminous than the Sun, with an absolute magnitude of -5.60. The Hipparcos astrometric data has estimated the distance of Eta Leonis to be roughly 400 parsecs from Earth, or 1,300 light years away.
There is evidence suggesting that Eta Leonis is part of a binary star system.
See also
- Lists of stars in the constellation Leo
References
- 1 2 3 4 5 Van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357.
- 1 2 3 4 5 6 Firnstein, M.; Przybilla, N. (2012). "Quantitative spectroscopy of Galactic BA-type supergiants. I. Atmospheric parameters". Astronomy & Astrophysics 543: A80. arXiv:1207.0308. Bibcode:2012A&A...543A..80F. doi:10.1051/0004-6361/201219034.
- ↑ Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters 32 (11): 759. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065.
- 1 2 3 Przybilla, N.; Butler, K.; Becker, S. R.; Kudritzki, R. P. (2006). "Quantitative spectroscopy of BA-type supergiants". Astronomy and Astrophysics 445 (3): 1099. arXiv:astro-ph/0509669. Bibcode:2006A&A...445.1099P. doi:10.1051/0004-6361:20053832.
- 1 2 3 4 Tanrıverdi, Taner (2013). "Elemental abundances of the supergiant stars σ Cygnus and η Leonis". New Astronomy 25: 50. arXiv:1512.04557. Bibcode:2013NewA...25...50T. doi:10.1016/j.newast.2013.03.013.
- ↑ Garrison, R. F. (December 1993), "Anchor Points for the MK System of Spectral Classification", Bulletin of the American Astronomical Society 25: 1319, Bibcode:1993AAS...183.1710G
External links
- Jim Kaler's Stars:Eta Leo
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