Pi2 Orionis (π2 Ori, π2 Orionis) is the Bayer designation for a solitary star in the equatorial constellation of Orion. Although the Bright Star Catalogue lists this as a spectroscopic binary star system,[10] this does not appear to be the case.[11] It is visible to the naked eye with an apparent visual magnitude of 4.35.[2] Based upon an annual parallax shift of 14.53 mas,[1] it is located roughly 224 light-years away from the Sun.
Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
---|---|
Constellation | Orion |
Right ascension | 04h 50m 36.72298s[1] |
Declination | +08° 54′ 00.6493″[1] |
Apparent magnitude (V) | 4.35[2] |
Characteristics | |
Spectral type | A1 Vn[3] |
U−B color index | +0.03[2] |
B−V color index | +0.01[2] |
Astrometry | |
Radial velocity (Rv) | 24[4] km/s |
Proper motion (μ) | RA: +1.41[1] mas/yr Dec.: −29.91[1] mas/yr |
Parallax (π) | 14.53 ± 0.38 mas[1] |
Distance | 224 ± 6 ly (69 ± 2 pc) |
Absolute magnitude (MV) | 0.48[5] |
Details | |
Radius | 2.7[6] R☉ |
Luminosity | 70[7] L☉ |
Surface gravity (log g) | 4.00±0.05[8] cgs |
Temperature | 9,457±128[8] K |
Metallicity [Fe/H] | −0.20±0.10[8] dex |
Rotational velocity (v sin i) | 261.4±13.5[5] km/s |
Other designations | |
Database references | |
SIMBAD | data |
This is an A-type main-sequence star with a stellar classification of A1 Vn,[3] where the 'n' indicates broad absorption lines due to rotation. It is spinning rapidly with a projected rotational velocity of 261.4 km/s.[5] This is giving the star an oblate shape with an equatorial bulge that is 13% larger than the polar radius.[12] It is shining with 70[7] times the solar luminosity from its outer atmosphere at an effective temperature of 9,457 K.[8]