The constellation of Cancer, the Crab. Cancer is a small but important constellation which lies in the northern hemisphere and is best seen on spring evenings. It is one of the twelve zodiacal constellations, lying between Leo and Gemini. It's most striking feature is the cluster of stars seen just above and left of centre. This is an open or galactic cluster called the Beehive (M44). Also known as Praesepe (the Manger) it lies some 520 light years away and contains around 300 stars. The two brightest stars in the image (seen at upper right) lie in Gemini and are known as Castor (upper right) and Pollux (lower left). See "Observing the Constellations", page 34.