NO Apodis
Star in the constellation Apus
From Wikipedia, the free encyclopedia
NO Apodis is a solitary,[15] red hued variable star located in the southern circumpolar constellation Apus. It has an average apparent magnitude of 5.86,[16] allowing it to be faintly seen with the naked eye. The object is relatively far at a distance of 790 light years[1] but is drifting closer with a heliocentric radial velocity −18.3 km/s.[7]
  | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Apus |
| Right ascension | 17h 31m 27.4667s[1] |
| Declination | −80° 51′ 32.876″[1] |
| Apparent magnitude (V) | 5.71-5.95[2] |
| Characteristics | |
| Evolutionary stage | AGB[3] |
| Spectral type | M3 III[4] |
| U−B color index | +1.80[5] |
| B−V color index | +1.67[5] |
| Variable type | Semiregular[6] |
| Astrometry | |
| Radial velocity (Rv) | −18.3±0.6[7] km/s |
| Proper motion (μ) | RA: −3.662 mas/yr[1] Dec.: −43.943 mas/yr[1] |
| Parallax (π) | 4.1479±0.0741 mas[1] |
| Distance | 790 ± 10 ly (241 ± 4 pc) |
| Absolute magnitude (MV) | −1.32[8] |
| Details | |
| Mass | 1.63[9] M☉ |
| Radius | 107[10] R☉ |
| Luminosity | 1,408[11] L☉ |
| Surface gravity (log g) | 1.7±0.1[12] cgs |
| Temperature | 3,521±122[10] K |
| Other designations | |
| 59 G. Apodis[13], NO Aps, NSV 8609, CD−80°638, CPD−80°828, FK5 1455, GC 23550, HD 156513, HIP 85760, HR 6429, SAO 258769[14] | |
| Database references | |
| SIMBAD | data |
NO Apodis has a stellar classification of M3 III,[4] indicating that it is a red giant. It is currently on the asymptotic giant branch,[3] fusing hydrogen and helium shells around an inert carbon core. At present it has 1.63 times the mass of the Sun[9] and an enlarged radius of 107 R☉.[10] It shines with a bolometric luminosity 1,408 times that of the Sun[11] from its photosphere at an effective temperature of 3,521 K.[10]
NO Apodis is classified as a semiregular variable of unknown subtype. Observations from Tabur et. al. (2009) reveal it to have two periods, both lasting 26-7 days.[17] During this timeframe, the star flucates between 5.71 and 5.95 in the visual band.[2]
| Period | Days | Amplitude |
|---|---|---|
| 1 | 26.2 | 0.04 |
| 2 | 26.6 | 0.092 |