Pi Puppis

π Puppis
Location of π Puppis (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Puppis
Right ascension 07h 17m 08.55678s
Declination −37° 05′ 50.8962″
Apparent magnitude (V) 2.69 – 2.76
Characteristics
Spectral type K3 Ib
U−B color index +1.238
B−V color index +1.608
Variable type SRd
Astrometry
Radial velocity (Rv)+15.8 km/s
Proper motion (μ) RA: −10.05 mas/yr
Dec.: +6.47 mas/yr
Parallax (π)4.04±0.33 mas
Distance810 ± 70 ly
(250 ± 20 pc)
Absolute magnitude (MV)−4.5
Details
Mass11.7±0.2 M
Radius235 R
Luminosity11,378 L
Surface gravity (log g)0.13 cgs
Temperature3,990–4,055 K
Age20.0±3.9 Myr
Other designations
π Pup, CPD−36°1211, FK5 278, GC 9706, HD 56855, HIP 35264, HR 2773, SAO 197795, PPM 283747, CCDM J07171-3706A, WDS J07171-3706A
Database references
SIMBADdata

Pi Puppis, Latinized from π Puppis, also named Ahadi, is the second-brightest star in the southern constellation of Puppis. It has an apparent visual magnitude of about 2.7, so it can be viewed with the naked eye at night. Parallax measurements yield an estimated distance of roughly 810 light-years (250 parsecs) from the Earth. This is a double star with a magnitude 6.86 companion at an angular separation of 0.72 arcsecond and a position angle of 148° from the brighter primary.