Astronomy:64 Eridani
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Eridanus |
| Right ascension | 04h 59m 55.73677s[2] |
| Declination | −12° 32′ 14.6983″[2] |
| Apparent magnitude (V) | 4.77[3] |
| Characteristics | |
| Spectral type | F0 V[4] |
| B−V color index | 0.266[3] |
| Variable type | δ Sct[5] |
| Astrometry | |
| Radial velocity (Rv) | −8.9±4.2[6] km/s |
| Proper motion (μ) | RA: +39.67[2] mas/yr Dec.: −87.04[2] mas/yr |
| Parallax (π) | 12.0106 ± 0.2199[7] mas |
| Distance | 272 ± 5 ly (83 ± 2 pc) |
| Absolute magnitude (MV) | 0.03[8] |
| Details | |
| Mass | 1.52[9] M☉ |
| Luminosity | 80.17[8] L☉ |
| Surface gravity (log g) | 3.37[9] cgs |
| Temperature | 7,346±250[9] K |
| Rotational velocity (v sin i) | 212[10] km/s |
| Age | 644[9] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
64 Eridani is a single,[12] yellow-white hued star in the constellation Eridanus having variable star designation S Eridani. It is faintly visible to the naked eye with an apparent visual magnitude of 4.77.[3] The annual parallax shift is measured at 12.01 mas, which equates to a distance of about 272 light years.[7] In addition to its proper motion, it is moving closer to the Sun with a radial velocity of around −9 km/s.[6]
This is an F-type main-sequence star with a stellar classification of F0 V.[4] It is catalogued a low amplitude Delta Scuti variable with a primary period of 0.273 days.[5] It was originally classified, tentatively, as an RR Lyrae variable of type 'c'.[13]
64 Eridani is spinning rapidly with a projected rotational velocity of 212 km/s.[10] This is giving the star an oblate shape with an equatorial bulge; its equatorial radius is 8% larger than its polar radius.[14] The star is an estimated 644 million years old with 1.5 times the mass of the Sun.[9] It is radiating 80[8] times the Sun's luminosity from its photosphere at an effective temperature of roughly 7,346 K.[9]
References
- ↑ Koen, Chris; Eyer, Laurent (March 2002). "New periodic variables from the Hipparcos epoch photometry". Monthly Notices of the Royal Astronomical Society 331 (1): 45–59. doi:10.1046/j.1365-8711.2002.05150.x. Bibcode: 2002MNRAS.331...45K.
- ↑ 2.0 2.1 2.2 2.3 van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, doi:10.1051/0004-6361:20078357, Bibcode: 2007A&A...474..653V.
- ↑ 3.0 3.1 3.2 Høg, E. et al. (2000), "The Tycho-2 catalogue of the 2.5 million brightest stars", Astronomy and Astrophysics 355: L27, doi:10.1888/0333750888/2862, Bibcode: 2000A&A...355L..27H.
- ↑ 4.0 4.1 Houk, Nancy; Smith-Moore, M. (1978), Michigan catalogue of two-dimensional spectral types for the HD stars, 4, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode: 1988mcts.book.....H.
- ↑ 5.0 5.1 Rodríguez, E.; Breger, M. (January 2001), "delta Scuti and related stars: Analysis of the R00 Catalogue", Astronomy and Astrophysics 366: 178–196, doi:10.1051/0004-6361:20000205, Bibcode: 2001A&A...366..178R.
- ↑ 6.0 6.1 de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics 546: 14, doi:10.1051/0004-6361/201219219, A61, Bibcode: 2012A&A...546A..61D.
- ↑ 7.0 7.1 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode: 2018A&A...616A...1G. Gaia DR2 record for this source at VizieR.
- ↑ 8.0 8.1 8.2 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode: 2012AstL...38..331A.
- ↑ 9.0 9.1 9.2 9.3 9.4 9.5 David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal 804 (2): 146, doi:10.1088/0004-637X/804/2/146, Bibcode: 2015ApJ...804..146D.
- ↑ 10.0 10.1 Royer, F. et al. (February 2007), "Rotational velocities of A-type stars. III. Velocity distributions", Astronomy and Astrophysics 463 (2): 671–682, doi:10.1051/0004-6361:20065224, Bibcode: 2007A&A...463..671R.
- ↑ "64 Eri". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=64+Eri.
- ↑ 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, doi:10.1111/j.1365-2966.2008.13596.x, Bibcode: 2008MNRAS.389..869E.
- ↑ Samus, N. N. et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1 61 (1): 80–88, doi:10.1134/S1063772917010085, Bibcode: 2017ARep...61...80S, http://www.sai.msu.su/gcvs/gcvs/, retrieved 2019-08-06.
- ↑ Belle, G. T. (2012). "Interferometric observations of rapidly rotating stars". The Astronomy and Astrophysics Review 20 (1): 51. doi:10.1007/s00159-012-0051-2. Bibcode: 2012A&ARv..20...51V.
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