Jump to content

Eta1 Coronae Australis

From Wikipedia, the free encyclopedia
(Redirected from Η1 Coronae Australis)
η1 Coronae Australis
Observation data
Epoch J2000      Equinox J2000
Constellation Corona Australis
Right ascension 18h 48m 50.49216s[1]
Declination −43° 40′ 48.1977″[1]
Apparent magnitude (V) 5.456[2]
Characteristics
Spectral type A3V[3]
B−V color index +0.13[4]
Astrometry
Radial velocity (Rv)−4.0±4.2[5] km/s
Proper motion (μ) RA: 22.312[1] mas/yr
Dec.: −14.139[1] mas/yr
Parallax (π)10.2735 ± 0.1889 mas[1]
Distance317 ± 6 ly
(97 ± 2 pc)
Absolute magnitude (MV)0.84[6]
Details
Radius2.2[7] R
Luminosity57.72[8] L
Surface gravity (log g)4.04[6] cgs
Temperature8371+4692
−444
[9] K
Rotational velocity (v sin i)122.3[10] km/s
Other designations
Eta1 CrA, CD−43° 12841, FK5 1490, HD 173715, HIP 92308, HR 7062, SAO 229299
Database references
SIMBADdata

Eta1 Coronae Australis, Latinized from η1 CrA, is a suspected astrometric binary[11] star system in the constellation of Corona Australis. It is visible to the naked eye as a dim, white-hued point of light with an apparent visual magnitude of 5.456.[2] Parallax measurements put it at a distance of 317 light-years away from the Sun.

The visible component is an A-type main-sequence star with a stellar classification of A3V,[3] which indicates it is generating energy through core hydrogen fusion. It has broad spectrum absorption lines associated with its rotation period, having a projected rotational velocity of 122.3 km/s.[10] The star is radiating 58[8] times the luminosity of the Sun from its photosphere at an effective temperature of 8,371 K.[9]

References

[edit]
  1. ^ a b c d e 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.
  2. ^ a b Høg, E.; et al. (2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27–L30. Bibcode:2000A&A...355L..27H.
  3. ^ a b Houk, Nancy (1978). Michigan catalogue of two-dimensional spectral types for the HD stars. Vol. 2. Ann Arbor: Dept. of Astronomy, University of Michigan. Bibcode:1978mcts.book.....H.
  4. ^ Johnson, H. L. (1966). "UBVRIJKL Photometry of the Bright Stars". Communications of the Lunar and Planetary Laboratory. 4: 99. Bibcode:1966CoLPL...4...99J.
  5. ^ Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID 119231169.
  6. ^ a b Philip, A. Davis; Egret, D. (1980). "An Analysis of the Hauck / Mermilliod Catalogue of Homgeneous Four-Color Data - Part Two". Astronomy and Astrophysics Supplement. 40: 199. Bibcode:1980A&AS...40..199P.
  7. ^ Pasinetti Fracassini, L. E.; et al. (February 2001). "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics". Astronomy and Astrophysics. 367 (2): 521–524. arXiv:astro-ph/0012289. Bibcode:2001A&A...367..521P. doi:10.1051/0004-6361:20000451. S2CID 425754.
  8. ^ a b 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.
  9. ^ a b Ammons, S. Mark; Robinson, Sarah E.; Strader, Jay; Laughlin, Gregory; Fischer, Debra; Wolf, Aaron (2006). "The N2K Consortium. IV. New Temperatures and Metallicities for More than 100,000 FGK Dwarfs". The Astrophysical Journal. 638 (2): 1004–1017. arXiv:astro-ph/0510237. Bibcode:2006ApJ...638.1004A. doi:10.1086/498490. S2CID 118834752.
  10. ^ a b Díaz, C. G.; González, J. F.; Levato, H.; Grosso, M. (2011). "Accurate stellar rotational velocities using the Fourier transform of the cross correlation maximum". Astronomy & Astrophysics. 531: A143. arXiv:1012.4858. Bibcode:2011A&A...531A.143D. doi:10.1051/0004-6361/201016386. S2CID 119286673.
  11. ^ 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.