Zeta Apodis, Latinized from ζ Apodis, is the Bayer designation for a star in the southern constellation of Apus. It has an apparent visual magnitude of +4.78,[2] 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 297 light-years (91 parsecs).[1]
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Apus |
Right ascension | 17h 21m 59.47633s[1] |
Declination | −67° 46′ 14.4072″[1] |
Apparent magnitude (V) | +4.78[2] |
Characteristics | |
Spectral type | K2 III[3] |
U−B color index | +1.27[2] |
B−V color index | +1.21[2] |
Astrometry | |
Radial velocity (Rv) | +12.6[4] km/s |
Proper motion (μ) | RA: –37.758[5] mas/yr Dec.: –7.637[5] mas/yr |
Parallax (π) | 10.8625 ± 0.1512 mas[5] |
Distance | 300 ± 4 ly (92 ± 1 pc) |
Absolute magnitude (MV) | −0.04[6] |
Details | |
Radius | 20[7] R☉ |
Luminosity | 154[6] L☉ |
Temperature | 4,388[8] K |
Other designations | |
Database references | |
SIMBAD | data |
The spectrum of Zeta Apodis matches a stellar classification of K2 III,[3] with the luminosity class of III indicating it is an evolved giant star. The measured angular diameter of this star, after correction for limb darkening, is 2.06 ± 0.02 mas.[10] At the estimated distance of Eta Draconis,[1] this yields a physical size of about 11 times the radius of the Sun.[7] The outer atmosphere has an effective temperature of 4,388 K,[8] which gives it the orange-hued glow of a K-type star.[11]
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.)[12]