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The Spring 2011 issue of The Earth Scientist is focused on modernizing seismology education. Thanks to IRIS, you can download this issue for free as a pdf. Print copies are available in our online store.
Cancer, the Crab is best viewed during the month of March.
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Cancer

Cancer, the Crab, is a member of the Zodiac, a group of constellations that the Sun travels through each year. Cancer is best seen during the month of March, but is visible from December through June. Although the Crab is one of the more famous constellations, it is mostly made of dim stars.

Fortunately, Cancer is surrounded by much brighter figures, like Gemini and Leo. If you use your imagination, a figure that looks like a crab appears. Looking at the picture, one can see a body with two "claws" coming out of it.

The constellation itself came from Greek myth. In the story of Heracles and the Twelve Labors, the warrior had a great battle with the monster Hydra. The giant crab tried to help Hydra, but Heracles smashed it with his foot. Hera put the crab in the sky because it was so brave.

Right next to the head is a star cluster known as Praesepe, or the Beehive. To the naked eye, it looks like a fuzzy cloud. Galileo later discovered that it was really a cluster of stars. It was named the Beehive because astronomers think the cluster looks like a swarm of bees.

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The Summer 2010 issue of The Earth Scientist, available in our online store, includes articles on rivers and snow, classroom planetariums, satellites and oceanography, hands-on astronomy, and global warming.

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