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Epsilon Doradus

Epsilon Doradus
Location of ε Doradus (circled)
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Dorado
Right ascension 05h 49m 53.52107s[1]
Declination −66° 54′ 04.2787″[1]
Apparent magnitude (V) 5.11[2]
Characteristics
Spectral type B6 V[3]
U−B color index −0.49[2]
B−V color index −0.14[2]
Variable type SPB[4]
Astrometry
Radial velocity (Rv)+15.5±1.6[5] km/s
Proper motion (μ) RA: −21.81[1] mas/yr
Dec.: +37.55[1] mas/yr
Parallax (π)5.68 ± 0.15 mas[1]
Distance570 ± 20 ly
(176 ± 5 pc)
Absolute magnitude (MV)−0.20[6]
Details
Mass4.31±0.05[7] M☉
Radius3.8±0.6[4] R☉
Luminosity556[7] L☉
Surface gravity (log g)3.89±0.20[4] cgs
Temperature13,212[7] K
Rotational velocity (v sin i)17[7] km/s
Age210[6] Myr
Other designations
ε Dor, CD−66°351, Gaia DR2 4659664312127365632, HD 39844, HIP 27534, HR 2064, SAO 249368, 2MASS J05495356-6654041[8]
Database references
SIMBADdata

Epsilon Doradus, Latinized from ε Doradus, is a solitary[9] star located in the southern constellation of Dorado. It is visible to the naked eye with an apparent visual magnitude of 5.11.[2] Based upon an annual parallax shift of 5.68 mas as measured from Earth, it is located roughly 570 light years from the Sun. At that distance, the visual magnitude of the star is diminished by an extinction factor of 0.09 due to interstellar dust.[6]

This is a B-type main sequence star with a stellar classification of B6 V.[3] It is a slowly pulsating B-type star with a mean longitudinal magnetic field strength of −64±26 G.[4] With 4.31[7] times the mass of the Sun and 3.8[4] times the Sun's radius, it is about 85% of the way through its main sequence lifetime.[7] The star is an estimated 210[6] million years old and is spinning with a projected rotational velocity of 17 km/s.[7] Epsilon Doradus radiates 556 times the solar luminosity from its photosphere at an effective temperature of 13,212 K.[7]

References

  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 Johnson, H. L. (1966), "UBVRIJKL Photometry of the Bright Stars", Communications of the Lunar and Planetary Laboratory, 4: 99, Bibcode:1966CoLPL...4...99J.
  3. ^ a b Houk, Nancy (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 1, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode:1978mcts.book.....H.
  4. ^ a b c d e Hubrig, S.; et al. (April 2009), "New magnetic field measurements of β Cephei stars and slowly pulsating B stars", Astronomische Nachrichten, 330 (4): 317, arXiv:0902.1314, Bibcode:2009AN....330..317H, doi:10.1002/asna.200811187, S2CID 17497112.
  5. ^ 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.
  6. ^ a b c d Gontcharov, G. A. (November 2012), "Spatial distribution and kinematics of OB stars", Astronomy Letters, 38 (11): 694–706, arXiv:1606.09028, Bibcode:2012AstL...38..694G, doi:10.1134/S1063773712110035, S2CID 119108982.
  7. ^ a b c d e f g h Zorec, J.; Royer, F. (January 2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy & Astrophysics, 537: A120, arXiv:1201.2052, Bibcode:2012A&A...537A.120Z, doi:10.1051/0004-6361/201117691, S2CID 55586789.
  8. ^ "eps Dor". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-04-14.
  9. ^ 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.
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