The band of constellations through which the Sun, Moon, and planets move in the course of a year. Of the 12 signs of the Zodiac, "Libra [the Balance] is the only nonliving figure among them. There are 8 1/2 animals and 4 1/2 humans in the zodiac. The predominance of animals gives us the name zodiac--from the same root as zoo." (Excerpted from 365 Starry Nights, by Chet Raymo.)

(Learn to pronounce the names of the Zodiac constellations by visiting A Skywatcher's Pronunciation Guide. Click on the hyperlinked symbol names to hear some of the sounds of the "zoo.")

Astrology is the religion which claims that your life is influenced by the alignment of the Sun, Moon, planets, and stars. Astronomy is the scientific study of outer space. Most astronomers do not believe in astrology. Who's right? Decide for yourself by visiting the following Web sites in which several astronomers present the case against astrology.

• Phil Plait's Bad Astronomy: What's Your Sign?
• The Real Constellations of the Zodiac
• Sun Signs: Astrolonomical vs. Astrological

Just for fun, construct a Zodiac Wheel (Adobe Acrobat PDF, 60K), that shows when Zodiac signs are visible in the night sky. Remember that signs of the Zodiac are "Sun signs," meaning that they appear in the day sky on your birthdate (the Sun is "in" your sign). For example, Leo (LEE-oh) is the fifth sign of the Zodiac for birthdates from 23 July to 22 August, but Leo is not visible in the late-July through late-August night skies. Beginning in February (six months after August), Leo is visible at night for a six-month period ending in July.