Sigma1 Cancri
Sigma1 Cancri is a binary star system in the zodiac constellation of Cancer. Its name is a Bayer designation that is Latinized from σ1 Cancri, and abbreviated Sigma1 Cnc or σ1 Cnc. The primary component is faintly visible to the naked eye, with an apparent visual magnitude of +5.68. Based upon an annual parallax shift of as seen from Earth, this star is located around from the Sun. It is moving further away with a line of sight velocity of −11 km/s.
This is a chemically peculiar A-type main sequence star with a stellar classification of A8 Vas. At an age of about 301 million years, Sigma1 Cancri is around 67% of the way through its main sequence lifespan. The star has 1.8 times the mass of the Sun and is radiating 18 times the Sun's luminosity from its photosphere at an effective temperature of.
There is a magnitude 13.3 companion at an angular separation of 5.2 arc seconds along a position angle of 276°, as of 2011. At that distance, the pair have a projected separation of. This star, designated Sigma1 Cancri B, has an estimated 62% of the mass of the Sun.