Pi Draconis, Latinized from π Draconis, is a solitary[7][4] star in the northern circumpolar constellation of Draco. It is visible to the naked eye with an apparent visual magnitude of 4.59.[2] Based upon an annual parallax shift of 14.25 mas as measured from Earth,[1] 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.[12]
Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
---|---|
Constellation | Draco |
Right ascension | 19h 20m 40.09333s[1] |
Declination | +65° 42′ 52.3095″[1] |
Apparent magnitude (V) | 4.59[2] |
Characteristics | |
Spectral type | A2 IIIs[3][4] |
U−B color index | +0.06[2] |
B−V color index | +0.02[2] |
Astrometry | |
Radial velocity (Rv) | −28.1±1.1[5] km/s |
Proper motion (μ) | RA: +15.09[1] mas/yr Dec.: +41.12[1] mas/yr |
Parallax (π) | 14.25 ± 0.12 mas[1] |
Distance | 229 ± 2 ly (70.2 ± 0.6 pc) |
Absolute magnitude (MV) | +0.37[6] |
Details | |
Mass | 2.70[7] M☉ |
Radius | 3.2[8] R☉ |
Luminosity | 60[9] L☉ |
Surface gravity (log g) | 3.80[10] cgs |
Temperature | 9,125[10] K |
Metallicity [Fe/H] | 0.42[6] dex |
Rotational velocity (v sin i) | 26±1[3] km/s |
Age | 350[7] Myr |
Other designations | |
Database references | |
SIMBAD | data |
With an age of 350 million years, this is an A-type star of stellar classification A2 IIIs,[3][4] 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,[10] meaning there are some chemical peculiarities. The measured angular size is 0.427±0.062 arc seconds.[12] At the estimated distance of Pi Draconis, this yields a physical size of about 3.2 times the radius of the Sun.[8] It has about 2.70[7] times the mass of the Sun and is radiating 60[9] times the solar luminosity from its photosphere at an effective temperature of 9,125 K.[10]