What Is the Constellation Cancer?

Significance

• Cancer is one of the zodiac constellations, which is a series of 12-star groupings that proceed around the sky along the path that the sun takes when viewed from the Earth.

Famous Ties

• The constellation has close ties to the myths involving Hercules. The Greeks believed that Cancer was a giant crab sent by the goddess Hera to bite Hercules as he fought the monstrous Hydra. After he killed the crab, she put it in the sky among the stars.

Fun Fact

• Cancer has two stars within its boundaries called Asellus Australis and Gamma Cancri, nicknamed the "southern ass" and the "northern ass."

Considerations

• Between Asellus Australis and Gamma Cancri is what appears to the unaided eye as a fuzzy area. In reality, it's Messier sky object 44, called the Praesepe, which is an open cluster of more than 300 stars.

Size

• The brightest star in cancer is Al Tarf, which is a faint star to the observer. However, it is about 660 times as bright as the sun. It's made faint from Earth because it is 290 light years away.