Pi Draconis
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Draco |
| Right ascension | 19h 20m 40.09333s |
| Declination | +65° 42′ 52.3095″ |
| Apparent magnitude (V) | 4.59 |
| Characteristics | |
| Spectral type | A2 IIIs |
| U−B color index | +0.06 |
| B−V color index | +0.02 |
| Astrometry | |
| Radial velocity (Rv) | −28.1±1.1 km/s |
| Proper motion (μ) | RA: +15.09 mas/yr Dec.: +41.12 mas/yr |
| Parallax (π) | 14.25±0.12 mas |
| Distance | 229 ± 2 ly (70.2 ± 0.6 pc) |
| Absolute magnitude (MV) | +0.37 |
| Details | |
| Mass | 2.70 M☉ |
| Radius | 3.2 R☉ |
| Luminosity | 60 L☉ |
| Surface gravity (log g) | 3.80 cgs |
| Temperature | 9,125 K |
| Metallicity [Fe/H] | 0.42 dex |
| Rotational velocity (v sin i) | 26±1 km/s |
| Age | 350 Myr |
| Other designations | |
| π Dra, 58 Dra, BD+65°1345, FK5 3547, HD 182564, HIP 95081, HR 7371, SAO 18299 | |
| Database references | |
| SIMBAD | data |
Pi Draconis, Latinized from π Draconis, is a solitary star in the northern circumpolar constellation of Draco. It is visible to the naked eye with an apparent visual magnitude of 4.59. Based upon an annual parallax shift of 14.25 mas as measured from Earth, it is located around 229 light years from the Sun. At that distance, the visual magnitude is diminished by an extinction factor of 0.063±0.10 due to interstellar dust.
With an age of 350 million years, this is an A-type star of stellar classification A2 IIIs, where the luminosity class of III typically indicates an evolved giant star and the 's' means the spectrum displays sharp absorption lines. It is a candidate Am star, meaning there are some chemical peculiarities. The measured angular size is 0.427±0.062 arc seconds. At the estimated distance of Pi Draconis, this yields a physical size of about 3.2 times the radius of the Sun. It has about 2.70 times the mass of the Sun and is radiating 60 times the solar luminosity from its photosphere at an effective temperature of 9,125 K.