The constellation of Cancer lies directly westward of Leo (that is, in the direct that the seated Lion is facing) making it easy to pick out in the sky. In shape, Cancer represents an inverted 'Y' shape, and the star Acubens (or Alpha Cancri) lies on one of the forks of the 'Y' shape in the southeast of the constellation.
The star takes its name Acubens from Arabic, meaning 'the claws' (that is, the claws of the Crab represented by Cancer). Though designated 'Alpha' Cancri, Acubens is in fact only the second brightest star in the constellation, with orange Tarf to the west being almost a full magnitude brighter.
Acubens is a white star that lies some 178 light years from the Solar System. This is a binary system, with the primary star (the component formally named Acubens) being on the main sequence, and therefore formally a dwarf star like the Sun. It is nonetheless considerably larger and hotter, with a diameter more than three times that of the Sun, and more than twenty times the luminosity. This primary star has at least one faint companion within the system, and there are some indications that it may have a second companion in a very close orbit.
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