Zeta Cancri
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Cancer |
| Right ascension | 08h 12m 12.726s |
| Declination | +17° 38′ 51.96″ |
| Apparent magnitude (V) | +5.58/+5.99/+6.12 |
| Characteristics | |
| Evolutionary stage | main-sequence star |
| Spectral type | F8V + G0V + G0IV-V |
| Astrometry | |
| Proper motion (μ) | RA: 27.61 mas/yr Dec.: −151.73 mas/yr |
| Parallax (π) | 39.87±0.82 mas |
| Distance | 82 ± 2 ly (25.1 ± 0.5 pc) |
| Orbit | |
| Primary | Zeta1 Cancri |
| Name | Zeta2 Cancri |
| Period (P) | 1,115 yr |
| Semi-major axis (a) | 7.7″ |
| Eccentricity (e) | 0.24 |
| Inclination (i) | 146° |
| Longitude of the node (Ω) | 74.2° |
| Details | |
| Zeta Cancri A | |
| Mass | 1.28 M☉ |
| Temperature | 6,230 K |
| Zeta Cancri B | |
| Mass | 1.18 M☉ |
| Temperature | 6,230 K |
| Zeta Cancri Ca | |
| Mass | 1.15 M☉ |
| Radius | 1.27±0.06 R☉ |
| Surface gravity (log g) | 4.27±0.10 cgs |
| Temperature | 6,008±80 K |
| Metallicity [Fe/H] | +0.10 dex |
| Rotational velocity (v sin i) | 1.5±1.0 km/s |
| Zeta Cancri Cb1 | |
| Mass | 0.50 M☉ |
| Temperature | 3,700 K |
| Metallicity [Fe/H] | +0.10 dex |
| Zeta Cancri Cb2 | |
| Mass | 0.50 M☉ |
| Temperature | 3,700 K |
| Metallicity [Fe/H] | +0.10 dex |
| Other designations | |
| ζ Cancri, 16 Cancri, BD+18°1867, GJ 9257, HIP 40167, ADS 6650, CCDM J08123+1738 | |
| Zeta1 Cancri A: Tegmen, Tegmine, ζ1 Cnc A, GC 11141 (A), HD 68257, HR 3208, SAO 97645 (A), WDS J08122+1739A | |
| Zeta1 Cancri B: ζ1 Cnc B, GC 11141 (B), HD 68255, HR 3209, SAO 97645 (B), WDS J08122+1739B | |
| Zeta2 Cancri: ζ2 Cnc, GC 11142, HD 68256, HR 3210, SAO 97646, WDS J08122+1739C | |
| Database references | |
| SIMBAD | data |
Zeta Cancri is a multiple star system in the constellation of Cancer. Its name is a Bayer designation that is Latinized from ζ Cancri, and abbreviated Zeta Cnc or ζ Cnc. This group is located approximately 82 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.
The system is constituted as follows:
- 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) 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.