E Ophiuchi
Star in the Ophiuchus constellation
From Wikipedia, the free encyclopedia
e Ophiuchi (HD 156681) is a star in the constellation Ophiuchus near the border with Hercules, which it had been mistakenly catalogued 66 Herculis.[7] It has an apparent magnitude of 5.03.
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Ophiuchus[1] |
| Right ascension | 17h 18m 36.99s[2] |
| Declination | +10° 51′ 52.1″[2] |
| Apparent magnitude (V) | 5.03[3] |
| Characteristics | |
| Evolutionary stage | red giant branch[4] |
| Spectral type | K4II-III[3] |
| U−B color index | 1.89[3] |
| B−V color index | 1.55[3] |
| R−I color index | 0.83[citation needed] |
| Astrometry | |
| Radial velocity (Rv) | 1.89 km/s |
| Proper motion (μ) | RA: +7.676[2] mas/yr Dec.: −97.830[2] mas/yr |
| Parallax (π) | 6.3784±0.1045 mas[2] |
| Distance | 511 ± 8 ly (157 ± 3 pc) |
| Absolute magnitude (MV) | −0.86[1] |
| Details | |
| Mass | 1.1[4] M☉ |
| Radius | 53[4] R☉ |
| Luminosity | 554[4] L☉ |
| Surface gravity (log g) | 1.06[4] cgs |
| Temperature | 3,836[4] K |
| Rotational velocity (v sin i) | 5.47[5] km/s |
| Age | 10.3[4] Gyr |
| Other designations | |
| e Oph, 66 Her, BD+11°3156, HD 156681, HR 6433, SAO 102725[6] | |
| Database references | |
| SIMBAD | data |
