Nu2 Canis Majoris
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Canis Major |
| Right ascension | 06h 36m 41.038s |
| Declination | −19° 15′ 21.17″ |
| Apparent magnitude (V) | 3.96 |
| Characteristics | |
| Evolutionary stage | Red-giant branch |
| Spectral type | K1 III |
| Astrometry | |
| Radial velocity (Rv) | +2.57±0.14 km/s |
| Proper motion (μ) | RA: +62.660 mas/yr Dec.: −69.816 mas/yr |
| Parallax (π) | 48.8490±0.1323 mas |
| Distance | 66.8 ± 0.2 ly (20.47 ± 0.06 pc) |
| Absolute magnitude (MV) | 2.47 |
| Details | |
| Mass | 1.439±0.047 M☉ |
| Radius | 5.198±0.060 R☉ |
| Luminosity | 13.2±0.7 L☉ |
| Surface gravity (log g) | 3.165±0.005 cgs |
| Temperature | 4,790±27 K |
| Metallicity [Fe/H] | 0.21±0.10 dex |
| Rotational velocity (v sin i) | 1.97±0.23 km/s |
| Age | 4.6±0.7 Gyr |
| Other designations | |
| ν2 CMa, 7 CMa, BD−19°1502, FK5 2510, GC 8624, GJ 239.1, HD 47205, HIP 31592, HR 2429, SAO 151702 | |
| Database references | |
| SIMBAD | data |
Nu2 Canis Majoris is a star in the southern constellation of Canis Major. Its name is a Bayer designation that is Latinized from ν2 Canis Majoris, and abbreviated Nu2 CMa or ν2 CMa. With an apparent visual magnitude of 3.96, it is bright enough to be seen with the naked eye, close to Sirius. An annual parallax shift of around 50.63 mas, as measured by the Gaia spacecraft, implies a distance of 66.8 light-years (20.5 pc). It is drifting further away with a line of sight velocity of +2.6 km/s. The star has two confirmed exoplanets and no known stellar companion.
This is an aging giant star with a stellar classification of K1 III, having exhausted the hydrogen at its core then expanded. It is believed to be on the early ascent of the red giant branch and has not yet undergone helium flash. This star is around 4.6 billion years old and is spinning slowly with a projected rotational velocity of 2 km/s. It has 1.4 times the mass of the Sun and has grown to 5.2 times the Sun's radius. The star is radiating 13 the luminosity of the Sun from its photosphere at an effective temperature of 4,790 K.