Observation data Epoch J2000.0 Equinox J2000.0 ( ICRS) | |
---|---|
Constellation | Cancer |
Right ascension | 09h 09m 21.53325s [1] |
Declination | +22° 02′ 43.6053″ [1] |
Apparent magnitude (V) | +5.15 [2] (5.70 + 6.20) [3] |
Characteristics | |
Spectral type | G9 III Fe-1 CH-0.5 [4] |
U−B color index | +0.75 [2] |
B−V color index | +0.96 [2] |
Astrometry | |
Radial velocity (Rv) | +7.7±0.3 [5] km/s |
Proper motion (μ) |
RA: −1.00
[1]
mas/
yr Dec.: −0.52 [1] mas/ yr |
Parallax (π) | 8.74 ± 0.49 mas [1] |
Distance | 370 ± 20
ly (114 ± 6 pc) |
Absolute magnitude (MV) | −0.12 [4] |
Orbit [6] [7] | |
Period (P) | 1,700.76 d |
Semi-major axis (a) | 0.0105±0.0017 [3]″ |
Eccentricity (e) | 0.06 |
Periastron epoch (T) | 2,428,876.86 ± 10.0 JD |
Argument of periastron (ω) (secondary) | 301.1° |
Semi-amplitude (K1) (primary) | 4.4 km/s |
Details | |
Luminosity | 118 [8] L☉ |
Temperature | 5,101 [8] K |
Other designations | |
Database references | |
SIMBAD | data |
Xi Cancri (ξ Cancri, abbreviated Xi Cnc, ξ Cnc) is a spectroscopic binary star system in the zodiac constellation of Cancer. It is visible to the naked eye with an apparent visual magnitude of +5.15. [2] Based upon parallax measurements obtained during the Hipparcos mission, [1] it is roughly 370 light-years distant from the Sun.
The two components are designated Xi Cancri A (formally named Nahn /ˈnɑːn/) [10] and B.
ξ Cancri ( Latinised to Xi Cancri) is the system's Bayer designation. The designations of the two components as Xi Cancri A and B derive from the convention used by the Washington Multiplicity Catalog (WMC) for multiple star systems, and adopted by the International Astronomical Union (IAU). [11]
Xi Cancri together with Lambda Leonis (Alterf) were the Persian Nahn, "the Nose", and the Coptic Piautos, "the Eye", both lunar asterisms. [12] Nahn was also the name given to Xi Cancri in a 1971 NASA technical memorandum. [13] In 2016, the IAU organized a Working Group on Star Names (WGSN) [14] to catalog and standardize proper names for stars. The WGSN decided to attribute proper names to individual stars rather than entire multiple systems. [15] It approved the name Nahn for the component Xi Cancri A on 1 June 2018 and it is now so included in the List of IAU-approved Star Names. [10]
At its present distance, the visual magnitude is diminished by an extinction factor of 0.135 due to interstellar dust. [3]
Xi Cancri is a single-lined spectroscopic binary star system with an orbital period of 4.66 years, an eccentricity of 0.06, and a semimajor axis of 0.01 arcsecond. The primary, Xi Cancri A, is a yellow G-type giant with an apparent magnitude of +5.70. Its companion, Xi Cancri B, is of magnitude 6.20. [3]