Zeta Apodis
Star in the constellation Apus
From Wikipedia, the free encyclopedia
Zeta Apodis is a star in the southern constellation of Apus. Its identifier is a Bayer designation that is Latinized from ζ Apodis, and abbreviated Zet Aps or ζ Aps, respectively. The star has an apparent visual magnitude of +4.78,[3] which is bright enough to allow it to be seen with the naked eye. The distance to this star is known from parallax measurements to be around 293 light-years (90 parsecs).[2] It is drifting further away with a heliocentric radial velocity of +11 km/s.[2]
 | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Apus[1] |
| Right ascension | 17h 21m 59.47769s[2] |
| Declination | −67° 46′ 14.4084″[2] |
| Apparent magnitude (V) | +4.78[3] |
| Characteristics | |
| Spectral type | K2 III[4] |
| U−B color index | +1.27[3] |
| B−V color index | +1.21[3] |
| Astrometry | |
| Radial velocity (Rv) | +11.38±0.12[2] km/s |
| Proper motion (μ) | RA: −37.437 mas/yr[2] Dec.: −7.925 mas/yr[2] |
| Parallax (π) | 11.1175±0.1047 mas[2] |
| Distance | 293 ± 3 ly (89.9 ± 0.8 pc) |
| Absolute magnitude (MV) | −0.04[1] |
| Details | |
| Mass | 1.51+0.99 −0.53[5] M☉ |
| Radius | 18.608[6] R☉ |
| Luminosity | 126±8[6] L☉ |
| Temperature | 4,486±125[6] K |
| Metallicity [Fe/H] | −0.30[5] dex |
| Other designations | |
| ζ Aps, CPD−67 3310, FK5 3374, HD 156277, HIP 84969, HR 6417, SAO 253882[7] | |
| Database references | |
| SIMBAD | data |
The spectrum of Zeta Apodis matches a stellar classification of K2 III,[4] with the luminosity class of III indicating it is an evolved giant star. Zeta Apodis has roughly 1.5 times the Sun's mass,[5] and expanded to 18 times the size of the Sun. It radiates 126 times the luminosity of the Sun from its photosphere at an effective temperature of 4,486 K,[6] giving it the orange-hued glow of a K-type star.[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 ζ Apodis, ι Apodis, β Apodis, γ Apodis, δ Octantis, δ1 Apodis, η Apodis, α Apodis and ε Apodis. Consequently, ζ Apodis itself is known as 異雀一 (Yì Què yī, English: the First Star of Exotic Bird.)[9]