Pi Canis Majoris

Pi Canis Majoris (π Canis Majoris; Latin for 'Greater Dog') is a binary star^[9] system in the southern constellation of Canis Major. It is visible to the naked eye, having an apparent visual magnitude of +4.69.^[2] Based upon an annual parallax shift of 33.80 mas as seen from Earth,^[1] this system is located 96.5 light years from the Sun. The star is moving in the general direction of the Sun with a radial velocity of −37.9 km/s. It will make its closest approach in around 733,000 years when it comes within 23 ly (7 pc).^[4]

Pi Canis Majoris

Observation data Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation	Canis Major
Right ascension	06h 55m 37.43099s[1]
Declination	−20° 08′ 11.3902″[1]
Apparent magnitude (V)	+4.69[2]
Characteristics
Spectral type	F1.5 V[3]
U−B color index	+0.06[2]
B−V color index	+0.36[2]
Astrometry
Radial velocity (Rv)	−37.9±5.5[4] km/s
Proper motion (μ)	RA: +51.50[1] mas/yr Dec.: +39.58[1] mas/yr
Parallax (π)	33.80±0.24 mas[1]
Distance	96.5 ± 0.7 ly (29.6 ± 0.2 pc)
Absolute magnitude (MV)	+2.06[5]
Details
π CMa A
Mass	1.32[6] M☉
Luminosity	9[7] L☉
Surface gravity (log g)	3.91[6] cgs
Temperature	6,863±233[6] K
Metallicity [Fe/H]	−0.18[3] dex
Rotational velocity (v sin i)	91.7±4.6[5] km/s
Age	763[6] Myr
Other designations
π CMa, 19 Canis Majoris, BD−19°1610, HD 51199, HIP 33302, HR 2590, SAO 172579, ADS 5602, CCDM 06556-2008[8]
Database references
SIMBAD	data

The brighter primary, component A, is an F-type main-sequence star with a stellar classification of F1.5 V.^[3] It is a periodic variable star with a frequency of 11.09569 cycles per day (2.16 hours per cycle) and an amplitude of 0.0025 in magnitude.^[10] The star has an estimated 1.32^[6] times the mass of the Sun and is radiating nine^[7] times the Sun's luminosity from its photosphere at an effective temperature of around 6,863 K.^[6] It displays a strong infrared excess at a wavelength of 24 μm and a weaker excess at 70 μm, indicating the presence of a circumstellar disk of dust with a temperature of 188 K, orbiting at 6.7 AU from the host star.^[11]

The magnitude 9.6 companion, component B, lies at an angular separation of 11.6 arc seconds from the primary as of 2008.^[9] Their projected separation is about 339 AU.^[11]

In popular culture

This star is the origin of the alien crystal, and the destination of starship Salvare, on Netflix show Another Life.

See also

• Canis Minor