10 Draconis
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Draco |
| Right ascension | 13h 51m 25.90451s |
| Declination | +64° 43′ 23.7510″ |
| Apparent magnitude (V) | 4.52 - 4.67 |
| Characteristics | |
| Evolutionary stage | AGB |
| Spectral type | M3.5 III |
| B−V color index | 1.572±0.010 |
| Variable type | LB: |
| Astrometry | |
| Radial velocity (Rv) | −12.26±0.17 km/s |
| Proper motion (μ) | RA: +14.144 mas/yr Dec.: +3.172 mas/yr |
| Parallax (π) | 8.2082±0.2628 mas |
| Distance | 400 ± 10 ly (122 ± 4 pc) |
| Absolute magnitude (MV) | −0.70 |
| Details | |
| Mass | 0.93±0.06 M☉ |
| Radius | 83.22+2.08 −2.16 R☉ |
| Luminosity | 1,031±70 L☉ |
| Surface gravity (log g) | 1.00 cgs |
| Temperature | 3,584±35 K |
| Metallicity [Fe/H] | −0.24 dex |
| Age | 10.24±1.40 Gyr |
| Other designations | |
| i Dra, 10 Dra, CU Dra, BD+65°963, FK5 511, HD 121130, HIP 67627, HR 5226, SAO 16199 | |
| Database references | |
| SIMBAD | data |
10 Draconis is a single star in the northern circumpolar constellation of Draco. It was a latter designation of 87 Ursae Majoris, and is visible to the naked eye with an apparent visual magnitude of about 4.6. The distance to this star, as determined from its annual parallax shift of 8.2 mas, is around 400 light years. It is moving closer with a heliocentric radial velocity of −12 km/s, and is expected to come to within 84 ly in about 8.6 million years.
Estimated to be around 10 billion years old, this is an aging red giant star with a stellar classification of M3.5 III. It is a periodic variable with a frequency of 11.98912 cycles per day and an amplitude of 0.0254 in magnitude. The spectrum does not show evidence of s-process enhancement. 10 Dra has 93% of the mass of the Sun but has expanded to about 83 times the Sun's radius. The star is radiating over 1,000 times the Sun's luminosity from its enlarged photosphere at an effective temperature of 3,584 K.