66 Cancri

66 Cancri
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Cancer
Right ascension 09h 01m 24.13000s
Declination +32° 15 08.2666
Apparent magnitude (V) 5.870 (5.95 + 8.56)
Characteristics
Evolutionary stage main sequence
Spectral type A2 V
B−V color index 0.088±0.007
Astrometry
Radial velocity (Rv)−12.8±2.9 km/s
Proper motion (μ) RA: +0.48 mas/yr
Dec.: +0.34 mas/yr
Parallax (π)6.8850±0.1020 mas
Distance474 ± 7 ly
(145 ± 2 pc)
Absolute magnitude (MV)0.14
Details
Mass2.73±0.11 M
Luminosity95.7+24.6
−19.5
 L
Surface gravity (log g)4.0 cgs
Temperature8,974+230
−224
 K
Rotational velocity (v sin i)183 km/s
Age162 Myr
Other designations
66 Cnc, BD+32°1829, HD 77104, HIP 44307, HR 3587, SAO 61202, WDS 09014+3215
Database references
SIMBADdata

66 Cancri is a binary star system near the northern border of the zodiac constellation of Cancer, located 474 light years away from the Sun. It is visible to the naked eye as a faint, white-hued star with a combined apparent visual magnitude of 5.87. The pair are moving closer to the Earth with a heliocentric radial velocity of −13 light years. As of 2003, the magnitude 8.56 companion was located at an angular separation of 4.43 along a position angle of 134° from the primary.

The brighter member of the system, designated component A, is an A-type main-sequence star with a stellar classification of A2 V. It is around 162 million years old with a high rate of spin, showing a projected rotational velocity of 183 km/s. Estimates of the mass of the star range from 1.7 up to 2.73 times the mass of the Sun. It is radiating 96 times the Sun's luminosity from its photosphere at an effective temperature of 8,974 K.