45 Eridani is a single[7] star located around 700 light years away from the Sun in the equatorial constellation of Eridanus. It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 4.91.[2] This body is moving away from the Earth with a heliocentric radial velocity of +15 km/s.[1]
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Eridanus |
| Right ascension | 04h 31m 52.66831s[1] |
| Declination | −00° 02′ 38.4407″[1] |
| Apparent magnitude (V) | 4.91[2] |
| Characteristics | |
| Evolutionary stage | giant |
| Spectral type | K0/1 III[3] |
| U−B color index | +1.41[4] |
| B−V color index | +1.32±0.04[2] |
| Astrometry | |
| Radial velocity (Rv) | +15.22±0.35[1] km/s |
| Proper motion (μ) | RA: −1.149[1] mas/yr Dec.: −7.655[1] mas/yr |
| Parallax (π) | 4.6579 ± 0.2082 mas[1] |
| Distance | 700 ± 30 ly (215 ± 10 pc) |
| Absolute magnitude (MV) | −1.59[2] |
| Details | |
| Radius | 50.06±1.73[1] R☉ |
| Luminosity | 787.9±40.1[1] L☉ |
| Surface gravity (log g) | 2.0[5] cgs |
| Temperature | 4322+58 −57[1] K |
| Metallicity [Fe/H] | −0.17[5] dex |
| Other designations | |
| Database references | |
| SIMBAD | data |
The stellar classification for this star is K0/1 III,[3] which indicates this is an aging K-type giant star that has exhausted the hydrogen supply at its core and expanded. It has reached 50[1] times the Sun's radius and is radiating 788[1] times the luminosity of the Sun from its swollen photosphere at an effective temperature of 4,322 K.[1]
References edit
- ^ a b c d e f g h i j k l m 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 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 Houk, N.; Swift, C. (1999). "Michigan catalogue of two-dimensional spectral types for the HD Stars". Michigan Spectral Survey. 5. Bibcode:1999MSS...C05....0H.
- ^ Mermilliod, J.-C. (1986). "Compilation of Eggen's UBV data, transformed to UBV (unpublished)". Catalogue of Eggen's UBV Data. Bibcode:1986EgUBV........0M.
- ^ a b 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.
- ^ "45 Eri". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-05-28.
- ^ 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.