Xi Cancri
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Cancer |
| Right ascension | 09h 09m 21.541s |
| Declination | +22° 02′ 43.58″ |
| Apparent magnitude (V) | +5.15 (5.70 + 6.20) |
| Characteristics | |
| Evolutionary stage | red giant branch |
| Spectral type | G9 III Fe-1 CH-0.5 |
| U−B color index | +0.75 |
| B−V color index | +0.96 |
| Astrometry | |
| Radial velocity (Rv) | +7.7±0.3 km/s |
| Proper motion (μ) | RA: −3.147 mas/yr Dec.: 9.159 mas/yr |
| Parallax (π) | 8.004±0.3286 mas |
| Distance | 410 ± 20 ly (125 ± 5 pc) |
| Absolute magnitude (MV) | −0.12 |
| Orbit | |
| Period (P) | 1,700.76 ± 2.7 d (4.6564 ± 0.0074 yr) |
| Semi-major axis (a) | 0.0105±0.0017" (≥ 103.0×106 km (0.689 AU)) |
| Eccentricity (e) | 0.06±0.05 |
| Periastron epoch (T) | 2428876.86±10.0 JD |
| Argument of periastron (ω) (secondary) | 301.1±38.3° |
| Semi-amplitude (K1) (primary) | 4.41±0.02 km/s |
| Details | |
| Mass | 3.40+0.11 −0.21 M☉ |
| Radius | 16.13+0.73 −0.66 R☉ |
| Luminosity | 149+12 −11 L☉ |
| Surface gravity (log g) | 2.62±0.07 cgs |
| Temperature | 5,025+9 −11 K |
| Rotational velocity (v sin i) | 2.1±1.0 km/s |
| Age | 271+54 −63 Myr |
| Other designations | |
| Nahn, ξ Cnc, 77 Cancri, BD+22°2061, FK5 1239, GC 12635, HD 78515, HIP 44946, HR 3627, SAO 80666, WDS J09094+2203AB | |
| Database references | |
| SIMBAD | data |
Xi Cancri is a binary star system in the zodiac constellation of Cancer. Its name is a Bayer designation that is Latinised from ξ Cancri, and abbreviated Xi Cnc or ξ Cnc. This system is faintly visible to the naked eye with a combined apparent visual magnitude of +5.15. Based upon parallax measurements, it is approximately 410 light-years distant from the Sun. At its present distance, the visual magnitude is diminished by an extinction factor of 0.135 due to interstellar dust. It is drifting further away with a line of sight velocity of +8 km/s.
The two components are designated Xi Cancri A (formally named Nahn, pronounced /ˈnɑːn/) and B. The primary component is an evolved giant star. The position of this system near the ecliptic means it is subject to lunar occultation.