Eta Draconis
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Draco |
| Right ascension | 16h 23m 59.48594s |
| Declination | +61° 30′ 51.1699″ |
| Apparent magnitude (V) | +2.73 |
| Characteristics | |
| Spectral type | G8 III |
| U−B color index | +0.70 |
| B−V color index | +0.91 |
| Astrometry | |
| Radial velocity (Rv) | –14.3 km/s |
| Proper motion (μ) | RA: –17.02 mas/yr Dec.: +56.95 mas/yr |
| Parallax (π) | 35.42±0.09 mas |
| Distance | 92.1 ± 0.2 ly (28.23 ± 0.07 pc) |
| Absolute magnitude (MV) | +0.58 |
| Details | |
| A | |
| Mass | 2.55±0.26 M☉ |
| Radius | 10.46–10.53 R☉ |
| Luminosity | 65.6±6.3 L☉ |
| Surface gravity (log g) | 2.82±0.11 cgs |
| Temperature | 5,018 K |
| Metallicity [Fe/H] | –0.088 dex |
| Rotational velocity (v sin i) | 8 km/s |
| Age | 650±100 Myr |
| B | |
| Mass | 0.672 M☉ |
| Radius | 0.577 R☉ |
| Luminosity | 0.206 L☉ |
| Temperature | 5,114 K |
| Other designations | |
| Aldibain, Athebyne, 14 Draconis, BD+61 1591, FK5 822, HD 148387, HIP 80331, HR 6132, NSV 7713, SAO 17074, WDS 16240+6131. | |
| Database references | |
| SIMBAD | data |
Eta Draconis (η Draconis, abbreviated Eta Dra, η Dra) is a binary star in the northern circumpolar constellation of Draco. Despite having an apparent visual magnitude of only +2.73, it is the second-brightest star in this generally faint constellation. Based upon parallax measurements collected during the Hipparcos mission, this star is located at a distance of about 92.1 light-years (28.2 parsecs) from the Sun.
The two components are designated Eta Draconis A (also named Athebyne /ˈæθɪbaɪn/) and B.