Zeta Cancri

ζ Cancri A/B/C

Location of ζ Cancri (circled)
Observation data Epoch J2000.0      Equinox J2000.0
Constellation	Cancer
Right ascension	08h 12m 12.7s
Declination	+17° 38′ 52″
Apparent magnitude (V)	+5.58/+5.99/+6.12
Characteristics
Evolutionary stage	main-sequence star
Spectral type	F7V + F9V + G0V
Other designations
Tegmen, Tegmine, 16 Cancri, HR 3208/3209/3210, HD 68257/68255/68256, BD+18°1867, HIP 40167, SAO 97645/97646, GC 11142/11141, ADS 6650, CCDM J08123+1738, WDS 08122+1739

Zeta Cancri (ζ Cancri, abbreviated Zeta Cnc, ζ Cnc) is a multiple star system in the constellation of Cancer. It is approximately 83.4 light-years from Earth, and has a combined apparent magnitude of +4.67. Since it is near the ecliptic, it can be occulted by the Moon and, very rarely, by planets.

The system is constituted as follows:^[1]

• A binary pair designated Zeta¹ Cancri or, alternatively, Zeta Cancri AB, the two components of which are themselves designated Zeta¹ Cancri A or, simply, Zeta Cancri A (formally also named Tegmine /ˈtɛɡmɪniː/, the traditional name of the Zeta Cancri system)^[2] and Zeta¹/Zeta Cancri B.
• A triple star system designated Zeta² Cancri or alternatively Zeta Cancri C, consisting of a single star primary, designated Zeta²/Zeta Cancri Ca, together with a secondary binary pair, designated Zeta²/Zeta Cancri Cb. The binary pair's two components are themselves designated Zeta²/Zeta Cancri Cb1 and Cb2.