39 Cancri

39 Cancri is a star in the constellation Cancer, located about 614 light years from the Sun in the Beehive Cluster (NGC 2632). It is a challenge to see with the naked eye, having an apparent visual magnitude of 6.39.[2] This object is moving further from the Earth with a heliocentric radial velocity of 34 km/s.[2]

39 Cancri
Observation data
Epoch J2000.0      Equinox J2000.0
ConstellationCancer
Right ascension08h 40m 06.41823s[1]
Declination+20° 00′ 28.0339″[1]
Apparent magnitude (V)6.39[2]
Characteristics
Spectral typeG8+ III-IIIb[3]
B−V color index0.98[2]
Astrometry
Radial velocity (Rv)33.88[2] km/s
Proper motion (μ) RA: −35.610[1] mas/yr
Dec.: −11.964[1] mas/yr
Parallax (π)5.3162 ± 0.0589 mas[1]
Distance614 ± 7 ly
(188 ± 2 pc)
Details
Mass2.88[2] M
Radius12[4] R
Luminosity105[2] L
Surface gravity (log g)2.70±0.11[5] cgs
Temperature4,954±25[2] K
Metallicity [Fe/H]+0.21±0.05[5] dex
Age460[2] Myr
Other designations
39 Cnc, BD+20°2158, HD 73665, HIP 42516, HR 3427, SAO 80333[6]
Database references
SIMBADdata

This is an evolved giant star with a stellar classification of G8+ III-IIIb,[3] indicating it has consumed the hydrogen at its core. It is 460[2] million years old with 2.88[2] times the mass of the Sun and about 12[4] times the Sun's radius. The star is radiating 105[2] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,954 K.[2]

References