Alpha Apodis (Alpha Aps, α Apodis, α Aps) is the brightest star in the southern circumpolar constellation of Apus, with an apparent magnitude of approximately 3.825. It had the Greek alpha designation as part of the constellation which Johann Bayer called Apis Indica in his 1603 Uranometria star atlas. With a declination of –79°, this is a circumpolar star for much of the southern hemisphere. It can be identified on the night sky by drawing an imaginary line through Alpha Centauri and Alpha Circini then extending it toward the south celestial pole.
Epoch J2000.0 Equinox J2000.0 (ICRS)
|Right ascension||14h 47m 51.71203s|
|Declination||−79° 02′ 41.1032″|
|Apparent magnitude (V)||3.825|
|U−B color index||+1.68|
|B−V color index||+1.43|
|R−I color index||+0.53|
|Radial velocity (Rv)||−1.1 km/s|
|Proper motion (μ)|| RA: −7.395 mas/yr |
Dec.: −15.726 mas/yr
|Parallax (π)||7.5519 ± 0.3237 mas|
|Distance||430 ± 20 ly |
(132 ± 6 pc)
|Absolute magnitude (MV)||−1.67|
|Luminosity (bolometric)||980 L☉|
This is a giant star with a stellar classification of K2.5III, indicating that this star has consumed the hydrogen at its core and has evolved away from the main sequence. It has expanded to an estimated radius of about 48 times the radius of the Sun and is emitting 980 times the Sun's luminosity. The photosphere has an effective temperature of 4,256 K, giving the star the characteristic orange hue of a K-type star. Based upon parallax measurements, this star is 430 ± 20 light-years from the Earth. It is not known to have a companion.
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 α Apodis, ζ Apodis, ι Apodis, β Apodis, γ Apodis, δ Octantis, δ1 Apodis, η Apodis, and ε Apodis. Consequently, α Apodis itself is known as 異雀八 (Yì Què bā, English: the Eighth Star of Exotic Bird.)
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- (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 29 日