Iota Herculis
Iota Herculis (ι Herculis, ι Her) is a fourth-magnitude variable star system in the constellation Hercules, consisting of at least four stars all about 139 parsecs (450 light-years) away. The brightest is a β Cephei variable, a pulsating star.
Historical view of the Hercules constellation showing Iota Herculis as one of the hero's feet | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Hercules |
| Right ascension | 17h 39m 27.8864s |
| Declination | +46° 00′ 22.795″ |
| Apparent magnitude (V) | 3.80 |
| Characteristics | |
| Spectral type | B3IV |
| U−B color index | –0.71 |
| B−V color index | –0.18 |
| Variable type | Beta Cephei |
| Astrometry | |
| Radial velocity (Rv) | –20.0 km/s |
| Proper motion (μ) | RA: 7.48 mas/yr Dec.: 4.53 mas/yr |
| Parallax (π) | 7.17 ± 0.13 mas |
| Distance | 455 ± 8 ly (139 ± 3 pc) |
| Absolute magnitude (MV) | –1.97 |
| Details | |
| Mass | 6.7 ± 0.1 M☉ |
| Radius | 5.29 ± 0.45 R☉ |
| Luminosity | 2,489 L☉ |
| Surface gravity (log g) | 3.82 ± 0.06 cgs |
| Temperature | 18,070 ± 294 K |
| Metallicity [Fe/H] | –0.40 dex |
| Rotational velocity (v sin i) | 6±1 km/s |
| Age | 37.8 ± 8.6 Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.