Gamma Apodis

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

Location of γ Apodis (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Apus
Right ascension 16h 33m 27.08379s[1]
Declination −78° 53′ 49.7372″[1]
Apparent magnitude (V) 3.86[2]
Characteristics
Spectral type G9 III[2]
U−B color index +0.62[3]
B−V color index +0.91[3]
Astrometry
Radial velocity (Rv) +5.7[2] km/s
Proper motion (μ) RA: –125.51[1] mas/yr
Dec.: –78.25[1] mas/yr
Parallax (π) 20.87 ± 0.16[1] mas
Distance 156 ± 1 ly
(47.9 ± 0.4 pc)
Details
Surface gravity (log g) 3.5[4] cgs
Temperature 5,040[4] K
Metallicity [Fe/H] –0.05[4] dex
Rotational velocity (v sin i) 2.7[2] km/s
Other designations
FK5 611, GJ 626.1, HD 147675, HIP 81065, HR 6102, SAO 257407.[5]

Gamma Apodis (γ Aps, γ Apodis) is the Bayer designation for a star in the southern circumpolar constellation of Apus. From parallax measurements, the distance to this star can be estimated as 156 light-years (48 pc).[1] It is visible to the naked eye with an apparent visual magnitude of 3.86.[2] A stellar classification of G9 III[2] identifies it as a giant star in the later stages of its evolution. It is an active X-ray source with a luminosity of 1.607 × 1030 erg s–1, making it one of the 100 strongest stellar X-ray sources within 50 parsecs of the Sun.[6]

Naming[edit]

In Chinese caused by adaptation of the European southern hemisphere constellations into the Chinese system, 異雀 (Yì Què), meaning Exotic Bird, refers to an asterism consisting of γ Apodis, ζ Apodis, ι Apodis, β Apodis, δ Octantis, δ1 Apodis, η Apodis, α Apodis and ε Apodis. Consequently, γ Apodis itself is known as 異雀四 (Yì Què sì, English: the Fourth Star of Exotic Bird.)[7]

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 e f da Silva, L. et al. (December 2009), Search for associations containing young stars (SACY). III. Ages and Li abundances, Astronomy and Astrophysics 508 (2): 833–839, arXiv:0909.0677, Bibcode:2009A&A...508..833D, doi:10.1051/0004-6361/200911736. 
  3. ^ a b 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. 
  4. ^ a b c Abia, C. et al. (November 1988), Abundances of light metals and NI in a sample of disc stars, Astronomy and Astrophysics 206 (1): 100–107, Bibcode:1988A&A...206..100A. 
  5. ^ gam Aps -- Star, SIMBAD Astronomical Object Database (Centre de Données astronomiques de Strasbourg), retrieved 2012-06-29. 
  6. ^ Makarov, Valeri V. (October 2003), The 100 Brightest X-Ray Stars within 50 Parsecs of the Sun, The Astronomical Journal 126 (4): 1996–2008, Bibcode:2003AJ....126.1996M, doi:10.1086/378164. 
  7. ^ (Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 29 日

External links[edit]