The Cancer Constellation
Doesn't Offer Much Of A Meal

For the backyard stargazer the Cancer constellation is at best a snack, compared to some of the banquets available. One of the faintest constellations, The crab constellation has no star brighter than 4th magnitude. In star magnitude lower is brighter, So Cancer is very faint to the naked eye.

Perhaps this is a consequence of failing at its task.

The goddess Hera sent Cancer to help the Hydra during its battle with Hercules.

The Crab was sent to attack Hercules and grabbed his foot or toe with his claw. Hercules was not impressed and proceeded to crush the crab.

Hera rewarded Cancer for his valor by placing him in the sky. Perhaps though as punishment for not distracting Hercules enough to help the Hydra win, his stars are some of the dimmest in the zodiac.

Cancer is relatively small among the constellations as well... with an area of only 505 square degrees. It lies between Gemini to the west and Leo to the east.

Lynx is to the north and Canis Minor and Hydra to the south. 

Right Ascension: 9 hours

Declination: 20 degrees

Visible between +90 and -60 degrees

Best seen in March at 9:00 PM local time

Named Stars: Acubens (Alpha Cancri) Altarf (Beta Cancri) Asellus Borealis (Gamma Cancri) Asellus Australis (Delta Cancri) Tegmen (Zeta 1 Cancri)

Cancer is best known as the constellation that the sun was in at its farthest point north. This was during the summer solstice. This became the Tropic of Cancer. In the southern hemisphere this point at the winter solstice is the Tropic of Capricorn.

Although due to precession, the sun is actually in Taurus as the constellations are defined by the International Astronomical Union at the time of the solstice.

Praesepe, open star cluster M44 is located in Cancer. M44, also known as the beehive cluster, is a large group of 6th magnitude and fainter stars. Because of its size it's best seen in binoculars.

M67 is a distant, faint cluster and requires a larger telescope.

The Delta Cancrids are a meteor shower lasting from December 14 to February 14. It peaks on January 17 each year, with only four meteors per hour.

Celestial Solar System › ZODIACS › Cancer