Pi2 Pegasi

π2 Pegasi
Location of π2 Pegasi (circled)
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Pegasus
Right ascension 22h 09m 59.24371s
Declination +33° 10 41.5976
Apparent magnitude (V) +4.28
Characteristics
Spectral type F5 III
B−V color index 0.471±0.012
Astrometry
Radial velocity (Rv)+5.1±0.9 km/s
Proper motion (μ) RA: −12.87±0.12 mas/yr
Dec.: −18.95±0.16 mas/yr
Parallax (π)12.40±0.17 mas
Distance263 ± 4 ly
(81 ± 1 pc)
Absolute magnitude (MV)0.21
Details
Mass2.48 M
Radius8.5±0.8 R
Luminosity102.9±2.6 L
Temperature6,300+298
−263
 K
Rotational velocity (v sin i)139.7 km/s
Age530 Myr
Other designations
π2 Peg, 29 Pegasi, BD+32°4352, FK5 835, HD 210459, HIP 109410, HR 8454, SAO 72077
Database references
SIMBADdata

π2 Pegasi, Latinized as Pi2 Pegasi, is a single star in the northern constellation Pegasus. It is yellow-white in hue and visible to the naked eye as a faint point of light with an apparent visual magnitude of +4.28. The distance to this object is approximately 263 light years based on parallax, and it is drifting further away with a radial velocity of +5 km/s. This star is an outlying member of the Ursa Major Moving Group.

This object has a stellar classification of F5 III, matching an aging giant star that has exhausted the supply of hydrogen at its core then cooled and expanded off the main sequence. At present it has 8.5 times the radius of the Sun. The star is 530 million years old with 2.48 times the Sun's mass. It shows a high rotation rate considering its evolutionary status, with a projected rotational velocity of 140 km/s. The star has been noted as a possible variable shell star. Pi2 Pegasi is radiating 103 times the Sun's luminosity from its swollen photosphere at an effective temperature of 6,300 K.