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
Distance156 ± 1 ly
(47.9 ± 0.4 pc)
Absolute magnitude (MV)+0.41[4]
Details
Surface gravity (log g)3.5[5] cgs
Temperature5,040[5] K
Metallicity [Fe/H]–0.05[5] 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[6]
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 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.[7]

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.)[8]

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. ^ Cardini, D. (January 2005), "Mg II chromospheric radiative loss rates in cool active and quiet stars", Astronomy and Astrophysics, 430: 303–311, arXiv:astro-ph/0409683, Bibcode:2005A&A...430..303C, doi:10.1051/0004-6361:20041440.
  5. ^ 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.
  6. ^ "gam Aps". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2012-06-29.
  7. ^ 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.
  8. ^ (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 29 日