75 Cancri

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75 Cancri
Observation data
Epoch J2000      Equinox J2000
Constellation Cancer
Right ascension  09h 08m 47.33104s[1]
Declination +26° 37′ 44.8062″[1]
Apparent magnitude (V) 5.98[2]
Spectral type G5 IV-V[2]
U−B color index +0.20[3]
B−V color index +0.65[3]
Radial velocity (Rv)9.7478(60)[2] km/s
Proper motion (μ) RA: −138.07[1] mas/yr
Dec.: −369.97[1] mas/yr
Parallax (π)32.004 ± 0.052[1] mas
Distance101.9 ± 0.2 ly
(31.25 ± 0.05 pc)
Period (P)19.412347(23) d
Semi-major axis (a)5.8696(96) mas
Eccentricity (e)0.19494(11)
Inclination (i)19.412347(23)°
Longitude of the node (Ω)171.892(85)°
Periastron epoch (T)JD 2453895.9025(24)
Argument of periastron (ω)
Semi-amplitude (K1)
26.4961(35) km/s
Semi-amplitude (K2)
30.7579(65) km/s
75 Cnc A
Mass1.173(24) M
Temperature6000 K
Metallicity [Fe/H]−0.09 dex
75 Cnc B
Mass1.011(21) M
Temperature5900 K
Other designations
BD+27° 1715, FK5 2724, GJ 9286, HD 78418, HIP 44892, HR 3626, SAO 80659[4]
Database references

75 Cancri (abbreviated to 75 Cnc) is a binary star in the constellation of Cancer. The system is located about 102 light-years (31 parsecs) away, based on its stellar properties.[2]

75 Cancri is a spectroscopic binary, which means the two stellar components are too close to be resolved, but periodic Doppler shifts in their spectra indicate orbital motion. In this case, light from both stars can be detected, and it is a double-lined spectroscopic binary; the orbital period of the system is 19.41 days, and the eccentricity of the system is 0.19494, implying a slightly elliptical orbit. The primary has a mass of 1.173 M, and is a G-type main-sequence star or subgiant. The secondary is less massive, at 1.011 M.[2]


  1. ^ a b c d e van Leeuwen, F.; et al. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357.
  2. ^ a b c d e f g Konacki, Maciej; et al. (2010). "High-precision Orbital and Physical Parameters of Double-lined Spectroscopic Binary Stars—HD78418, HD123999, HD160922, HD200077, and HD210027". The Astrophysical Journal. 719 (2): 1293–1314. arXiv:0910.4482. Bibcode:2010ApJ...719.1293K. doi:10.1088/0004-637X/719/2/1293.
  3. ^ a b Mermilliod, J.-C. (1986). "Compilation of Eggen's UBV data, transformed to UBV (unpublished)". Catalogue of Eggen's UBV Data. Bibcode:1986EgUBV........0M.
  4. ^ "* 75 Cnc". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 21 August 2017.