Cancer, a constellation and the fourth sign of the zodiac. Cancer is the Latin name for crab; presumably, the unknown person who named it thought the constellation resembled that animal in shape. The Tropic of Cancer, an imaginary line 23 27' north of the Equator, marks the northernmost points reached by the sun's vertical rays. It is so named because in ancient times the sun was highest in the northern sky when it was in the same area of the sky as Cancer.
The moon is often the largest object in the sky outside of the sun. What is the moon made of, how did it form -- and why do people blame it for their strange behavior?
One tragic, moonless night in April 1912, the Titanic slid into the depths of the North Atlantic Ocean -- for good. A crew of Texas State academics suggested that Earth's favorite satellite may have some explaining to do.