Astronomy:Gamma Apodis

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Short description: Star in the constellation Apus
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
Equinox J2000.0]] (ICRS)
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: –126.122 ± 0.688[4] mas/yr
Dec.: –78.699 ± 0.667[4] mas/yr
Parallax (π)21.7674 ± 0.5542[4] mas
Distance150 ± 4 ly
(46 ± 1 pc)
Absolute magnitude (MV)+0.41[5]
Details
Surface gravity (log g)3.5[6] cgs
Temperature5,040[6] K
Metallicity [Fe/H]–0.05[6] 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, CPD–78° 1103[7]
Database references
SIMBADdata

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 150 ± 4 light-years (46.0 ± 1.2 pc).[4] 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.[8]

Naming

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).[9]

References

  1. 1.0 1.1 van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, doi:10.1051/0004-6361:20078357, Bibcode2007A&A...474..653V. 
  2. 2.0 2.1 2.2 2.3 2.4 2.5 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, doi:10.1051/0004-6361/200911736, Bibcode2009A&A...508..833D. 
  3. 3.0 3.1 Johnson, H. L. et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory 4 (99): 99, Bibcode1966CoLPL...4...99J. 
  4. 4.0 4.1 4.2 4.3 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode2018A&A...616A...1G. 
  5. Cardini, D. (January 2005), "Mg II chromospheric radiative loss rates in cool active and quiet stars", Astronomy and Astrophysics 430: 303–311, doi:10.1051/0004-6361:20041440, Bibcode2005A&A...430..303C. 
  6. 6.0 6.1 6.2 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, Bibcode1988A&A...206..100A. 
  7. "gam Aps". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=gam+Aps. 
  8. Makarov, Valeri V. (October 2003), "The 100 Brightest X-Ray Stars within 50 Parsecs of the Sun", The Astronomical Journal 126 (4): 1996–2008, doi:10.1086/378164, Bibcode2003AJ....126.1996M. 
  9. (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 29 日