Epsilon Crateris

Summary

Epsilon Crateris (ε Crateris) is a solitary[12] star in the southern constellation of Crater. Visible to the naked eye, it has an apparent visual magnitude of 4.84.[2] It is located in the sky above Beta Crateris, and slightly to the left, or east, marking the lower right edge of the rim of the bowl and is somewhat closer to Theta Crateris, which is further east at the top of the bowl. With an annual parallax shift of 8.67[1] mas as seen from the Earth, its estimated distance is around 376 light years from the Sun.

ε Crateris
Location of ε Crateris (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Crater
Right ascension 11h 24m 36.59019s[1]
Declination −10° 51′ 33.5591″[1]
Apparent magnitude (V) 4.84[2]
Characteristics
Spectral type K5 III[3]
U−B color index +1.87[2]
B−V color index +1.55[2]
Astrometry
Radial velocity (Rv)+2.0±0.6[4] km/s
Proper motion (μ) RA: −25.65[1] mas/yr
Dec.: +24.96[1] mas/yr
Parallax (π)8.9013 ± 0.2019 mas[5]
Distance366 ± 8 ly
(112 ± 3 pc)
Absolute magnitude (MV)−0.43±0.18[6]
Details
Mass0.99±0.08[6] M
Radius44.7[7] R
Luminosity391[8] L
Surface gravity (log g)1.61[9] cgs
Temperature3,930[9] K
Metallicity [Fe/H]−0.38[9] dex
Rotational velocity (v sin i)10[10] km/s
Other designations
ε Crt, 14 Crateris, BD−10° 3260, HD 99167, HIP 55687, HR 4402, SAO 156658.[11]
Database references
SIMBADdata
Image showing the constellation Crater as a bowl, with ε marking the rim

This is an evolved K-type giant star with a stellar classification of K5 III.[3] It has about the same mass as the Sun, but has expanded to 44.7[7] times the Sun's radius. The star is radiating 391[8] times the solar luminosity from its outer atmosphere at an effective temperature of 3,930 K.[9]

References edit

  1. ^ a b c d e van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357, S2CID 18759600.
  2. ^ a b c d Mermilliod, J.-C. (1986), "Compilation of Eggen's UBV data, transformed to UBV (unpublished)", Catalogue of Eggen's UBV Data, SIMBAD, Bibcode:1986EgUBV........0M.
  3. ^ a b Houk, N.; Swift, C. (1999), "Michigan catalogue of two-dimensional spectral types for the HD Stars", Michigan Spectral Survey, 5, Ann Arbor, Michigan: Department of Astronomy, University of Michigan, Bibcode:1999MSS...C05....0H.
  4. ^ 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, arXiv:1208.3048, Bibcode:2012A&A...546A..61D, doi:10.1051/0004-6361/201219219, S2CID 59451347, A61.
  5. ^ 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.
  6. ^ a b da Silva, L.; et al. (November 2006), "Basic physical parameters of a selected sample of evolved stars", Astronomy and Astrophysics, 458 (2): 609–623, arXiv:astro-ph/0608160, Bibcode:2006A&A...458..609D, doi:10.1051/0004-6361:20065105, S2CID 9341088.
  7. ^ a b Setiawan, J.; et al. (July 2004), "Precise radial velocity measurements of G and K giants. Multiple systems and variability trend along the Red Giant Branch", Astronomy and Astrophysics, 421: 241–254, Bibcode:2004A&A...421..241S, doi:10.1051/0004-6361:20041042-1.
  8. ^ a b McDonald, I.; et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society, 427 (1): 343–57, arXiv:1208.2037, Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x, S2CID 118665352.
  9. ^ a b c d McWilliam, Andrew (December 1990), "High-resolution spectroscopic survey of 671 GK giants", Astrophysical Journal Supplement Series, 74: 1075–1128, Bibcode:1990ApJS...74.1075M, doi:10.1086/191527.
  10. ^ Bernacca, P. L.; Perinotto, M. (1970), "A catalogue of stellar rotational velocities", Contributi Osservatorio Astronomico di Padova in Asiago, 239 (1): 1, Bibcode:1970CoAsi.239....1B.
  11. ^ "* eps Crt -- Star". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-03-01.{{cite web}}: CS1 maint: postscript (link)
  12. ^ 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.