Cancer
Origin
Cancer represents a crab that was crushed by Heracles while he was fighting the Dragon (Draco), after which the goddess Hera placed the crab among the stars. Some early modern drawings also represent these stars with the image of a lobster, but the original Babylonian image was the Seat of the God of Heaven, represented by the quadrilateral of stars boxing the open star cluster M44.
Bright Stars
The brightest star in Cancer is Altarf or Beta Cancri, which has an apparent magnitude of 3.76; it is a double star containing a K-type giant star and its faint red dwarf companion. The next-brightest stars are Delta Cancri, Iota Cancri, and Alpha Cancri at magnitude 4.17, 4.20, and 4.27, respectively.
Photo of the constellation Cancer produced by NOIRLab in collaboration with Eckhard Slawik, a German astrophotographer.
The annotations are from a standardized set of 88 western IAU constellations and stick figures from Sky & Telescope. Please find here a non-annotated version of the image.
Credit: E. Slawik/NOIRLab/NSF/AURA/M. Zamani
Latin name
English name
Cancer
Pronunciation
KAN-surr
Abbreviation
Cnc
Notable Objects
Notable objects in Cancer include Messier 44, also known as NGC 2632, an open star cluster about 600 light-years away. Messier 44 is bright enough to be seen with the naked eye in a dark area.
Messier 67, or NGC 2682, is another open star cluster nearly 3000 light-years away. Messier 67 is on the very edge of naked eye visibility for those with excellent vision under very dark skies, but will be relatively easy to see with binoculars or a small telescope.
