by Tony Chiodo

Created on: November 24, 2008

A working knowledge of the night-time sky can enormously enrich one's nocturnal hours and provide an exhilarating perspective on our very existence. Here is a basic guide to some of the more prominent celestial attractions.

SPRING

The key grouping is the Big Dipper, an asterism of the constellation Ursa Major, the Great Bear. In Spring the dipper is upside down, above Polaris.

The two outside stars, now on the left, are the pointers. An imaginary line extended downward, five times the distance between the pointers, will bring you to Polaris, the famous North Star, and the tail star of the Little Dipper.

Polaris is very close to the north celestial pole and nearly in a direct line with the earth's rotational axis. Therefore, it remains almost motionless while the rest of the stars and constellations slowly revolve around it, making a complete circuit every 24 hours.

The Dipper can locate other treasures:

Extend the curving handle outward and it will lead to the dazzling orange Arcturus, which is part of the constellation Bootes, an upside down, elongated diamond. Immediately to the right is the lovely Corona Borealis, the Northern Crown, a glittering curve of jewels.

By following the handle out beyond Arcturus you come to a blue giant, Spica, in the constellation Virgo.

If you reverse that line through the pointers and extend it upward you will come to a bright 1st magnitude star, Regulus, "Little King", which is part of the constellation Leo, and lies on the ecliptic, the path that the sun and the planets travel as they make their way across the sky.

Below Polaris you might notice a stray letter of the alphabet. This is Cassiopeia, a somewhat flattened "W" ("M" in the Fall), actually a vain queen on her throne, who boasted of her flawless beauty. Cassiopeia and the Dipper remain opposite each other as they rotate around Polaris.

Facing south, to the right of Leo is Gemini, two long parallel lines topped by the twins Pollux and Castor.

Leo, Gemini and Virgo are all constellations of the Zodiac, an annual cycle of 12 zones along the aforementioned ecliptic. Some of them, like Cancer and Pisces, are faint and difficult to see.

SUMMER

Now the Big Dipper has swung around to the west of Polaris. Cassiopeia is higher and better placed for viewing. Straight up from the "Queen" is the white supergiant, Deneb,(Arabic for ""tail") which forms the head of the well-known Northern Cross, itself an asterism of the constellation Cygnus, the Swan.

Looking south, it is easy to pick out the

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