The patch of sky that appears overhead about 7 p.m. in early December is informally known as “the celestial sea.” That’s because it is home to all forms of watery constellations, including Delphinus the Dolphin, Capricornus the Sea Goat, Cetus the Whale, Eridanus the River, Aquarius the Water Carrier and Piscis Austrinus the Southern Fish.

In the middle of the celestial sea is the zodiacal constellation of Pisces the Fishes. This pair of fish represents the mythological characters of Venus and her son, Cupid. According to legend, Venus and Cupid were strolling along the banks of the Euphrates River one day when the monster Typhon appeared. Typhon was at war with the gods and was attempting to take control of the universe from Jupiter. The gods and goddesses changed themselves into all sorts of animals to hide and escape from him. On this occasion, Venus and Cupid transformed themselves into fish and dove into the river, where the fire-breathing Typhon could not follow.

Although Pisces has no bright, flashy stars, it is nonetheless rather easy to spot because of its distinctive pattern. Just south of the Great Square of Pegasus, you’ll find a small circle formed from seven stars. Nicknamed “the Circlet,” this pattern represents Venus in the form of a fish. A faint stream of stars representing a ribbon trails off behind the Circlet eastward to Pisces’ alpha star named Alrischa, meaning “the Knot.” Another stream of faint stars extends northward from Alrischa to a triangle of stars on the eastern side of the Great Square, representing Cupid in the form of a fish.

Pisces occupies an important crossroad of the sky. It is here where the sky’s celestial equator and the sun’s path, called the ecliptic, cross each other on the first day of spring each year. When the sun reaches this point, called the vernal equinox, spring begins in the northern hemisphere. In 2009, this will happen at 5:44 a.m. MST on March 20. Of course, when this occurs, the stars of Pisces will be hidden behind the sun in our daytime sky, so step outside this month to catch a glimpse of this delightful constellation.