Zeta Arae

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ζ Arae
Diagram showing star positions and boundaries of the Ara constellation and its surroundings
Cercle rouge 100%.svg

Location of ζ Arae (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Ara
Right ascension 16h 58m 37.21217s[1]
Declination –55° 59′ 24.5203″[1]
Apparent magnitude (V) 3.13[2]
Characteristics
Spectral type K3 III[3]
U−B color index +1.96[2]
B−V color index +1.60[2]
Astrometry
Radial velocity (Rv) –6.0[4] km/s
Proper motion (μ) RA: –17.80[1] mas/yr
Dec.: –36.67[1] mas/yr
Parallax (π) 6.71 ± 0.19[1] mas
Distance 490 ± 10 ly
(149 ± 4 pc)
Absolute magnitude (MV) –3.95[5]
Details
Surface gravity (log g) 1.50[6] cgs
Temperature 4,350[6] K
Metallicity [Fe/H] –0.40[6] dex
Other designations
Tseen Yin, SAO 244315, HD 152786, FK5 631, HIP 83081, HR 6285.[7]
Database references
SIMBAD data
Data sources:
Hipparcos Catalogue,
CCDM (2002),
Bright Star Catalogue (5th rev. ed.)

Zeta Arae (ζ Ara, ζ Arae) is a star in the southern constellation Ara. It is sometimes is called by the name Tseen Yin, together with δ Arae.[8] The apparent visual magnitude of this star is 3.1,[2] which can be seen from suburban skies in the southern hemisphere. From the parallax measurements, it is located at a distance of 490 light-years (150 parsecs) from Earth.[1]

The spectrum of this star matches a stellar classification of K3 III.[3] The luminosity class of 'III' indicates this is a giant star that has exhausted the hydrogen at its core and evolved away from the main sequence. It is radiating energy from its outer atmosphere at an effective temperature of 4,350 K,[6] which is what gives it the orange hue of a K-type star.[9] This star displays an excess of infrared emission that may indicate circumstellar matter.[10]

In Chinese, (Guī), meaning Tortoise, refers to an asterism consisting of ζ Arae, ε1 Arae, γ Arae, δ Arae and η Arae.[11] Consequently, ζ Arae itself is known as 龜五 (Guī wǔ, English: the Fifth Star of Tortoise.)[12]

References[edit]

  1. ^ a b c d e f van Leeuwen, F. (November 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 
  2. ^ a b c d Johnson, H. L. et al. (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 (1978), Michigan catalogue of two-dimensional spectral types for the HD stars 1, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode:1975mcts.book.....H 
  4. ^ Wielen, R. et al. (1999), Sixth Catalogue of Fundamental Stars (FK6). Part I. Basic fundamental stars with direct solutions (35), Astronomisches Rechen-Institut Heidelberg, Bibcode:1999VeARI..35....1W 
  5. ^ Jasniewicz, G. et al. (February 1999), "Late-type giants with infrared excess. I. Lithium abundances", Astronomy and Astrophysics 342: 831–838, Bibcode:1999A&A...342..831J 
  6. ^ a b c d Jones, K. L. et al. (June 1992), "Spectroscopic investigation of cool giants and the authenticity of their reported microwave emission", Monthly Notices of the Royal Astronomical Society 256 (3): 535–544, Bibcode:1992MNRAS.256..535J 
  7. ^ "zet Ara -- Star", SIMBAD (Centre de Données astronomiques de Strasbourg), retrieved 2012-01-05 
  8. ^ Allen, R. H. (1963). Star Names: Their Lore and Meaning (Reprint ed.). New York, NY: Dover Publications Inc. p. 64. ISBN 0-486-21079-0. 
  9. ^ "The Colour of Stars", Australia Telescope, Outreach and Education (Commonwealth Scientific and Industrial Research Organisation), December 21, 2004, retrieved 2012-01-16 
  10. ^ Plets, H. et al. (July 1997), "Giants with infrared excess", Astronomy and Astrophysics 323: 513–523, Bibcode:1997A&A...323..513P 
  11. ^ (Chinese) 中國星座神話, written by 陳久金. Published by 台灣書房出版有限公司, 2005, ISBN 978-986-7332-25-7.
  12. ^ (Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 1 日

External links[edit]