Pi2 Orionis

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.

For other stars with this Bayer designation, see Pi Orionis.

π² Orionis

Location of π2 Orionis (circled)
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
π2 Ori, 2 Orionis, BD+08°777, HD 30739, HIP 22509, HR 1544, SAO 112124[9]
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]