Kappa1 Apodis
Kappa1 Apodis, Latinized from κ1 Apodis, is the Bayer designation for a binary star system in the southern circumpolar constellation of Apus. Based upon parallax measurements, it is located roughly 1,060 light-years (325 parsecs) from Earth. The combined apparent visual magnitude of the system is 5.52, indicating that this is a faint, naked eye star that can be viewed in dark suburban skies. It is moving away from the Sun with a radial velocity of +62 km/s.
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Apus |
| Right ascension | 15h 31m 30.82213s |
| Declination | −73° 23′ 22.5295″ |
| Apparent magnitude (V) | 5.52 |
| Characteristics | |
| Spectral type | B1npe |
| U−B color index | −0.791 |
| B−V color index | −0.128 |
| Variable type | γ Cas |
| Astrometry | |
| Radial velocity (Rv) | +62 km/s |
| Proper motion (μ) | RA: +0.996 mas/yr Dec.: −18.345 mas/yr |
| Parallax (π) | 3.0798 ± 0.0717 mas |
| Distance | 1,060 ± 20 ly (325 ± 8 pc) |
| Absolute magnitude (MV) | −2.47 |
| Details | |
| Mass | 12.0±0.3 M☉ |
| Luminosity | 2,120 L☉ |
| Surface gravity (log g) | 3.90 cgs |
| Temperature | 21,500 K |
| Age | 5.6±1.0 Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is a spectroscopic binary system with an orbital period of 0.6 days. The combined spectrum matches a stellar classification of B1npe. The 'e' suffix indicates that this is a Be star with emission lines in the spectrum. An 'n' means that the absorption lines in the spectrum are broadened from the Doppler effect as a result of rapid rotation. Finally, the 'p' shows some peculiarity in the spectrum. It is classified as a Gamma Cassiopeiae type variable star and its brightness varies from magnitude +5.43 to +5.61.
This is a runaway star with a peculiar velocity of 69.8±4.7 km/s. Because it is a binary star system, it was most likely not turned into a runaway system as the result of a supernova explosion. A companion star is a 12th magnitude orange K-type subgiant located at an angular separation of 27 arcseconds.