Kaye Corbett, age 12, of Richmond, Virginia, for her question:

Is there a planet named Andromeda?

A planet must orbit around a starry sun just as our earth does. Astronomers tell us that the Universe has millions of stars that have families of orbiting planets. If people live there, we don't know what they call their home planets. For all we know, one of the many millions just might be called Andromeda. But our starry sun does not have a planet by this name.

There is something up in our starry sky called Andromeda    but it is not a planet. It is a group of stars called a constellation. A constellation is a recognizable pattern of stars occupying certain parts of the sky. For example, the Big Dipper constellation swings around the North Star, which is in the Little Dipper constellation.

Several constellations are up there around the North Star every night of the year. But other constellations can be seen only in spring or summer, fall or winter. A good time to see the constellation Andromeda is in the fall. It is a long thin triangle and not very easy to find.

To locate it, first find the Big Dipper and let its two pointers point you to the North Star. Continue across the sky to the constellation Cassiopeia, which is shaped like a bejeweled letter "W". Continue on to the four bright stars that form the Great Square of Pegasus. Notice the corner star nearest to Cassiopeia. Its name is Alpheratz    and Pegasus shares this star with Andromeda.

The constellations were named in ancient days, usually for fabled gods or heros or sacred animals. The hero Perseus rode the winged horse Pegasus and rescued the lady Andromeda, who was chained to the rocks. The ancients drew pictures of these fabled creatures around the constellations. The bright star Alpheratz in the wing of Pegasus also marks the head of the lady Andromeda. The thin triangle of stars mark the two sides of her body.

One of these lines marked her chained hand. And long before telescopes, even the ancients observed something mysterious in this region of Andromeda. On a clear starry night, you just may be able to see this something as a small hazy patch of light. A powerful telescope shows that this hazy spot is an enormous galaxy of perhaps a hundred billion starry suns.

In a telescope picture, this stupendous sight looks somewhat like a glowing white daisy, bowing his head. The bright center is crowded with countless blazing stars and out from the center there are starry spiraling arms. This dazzling galaxy is called the Andromeda Nebula  ¬or the Great Spiral Nebula in Andromeda.

The sun has no planet named Andromeda. But from the planet Earth we can see the starry constellation named Andromeda and sometimes get a glimpse of the Great Nebula called Andromeda. Astronomers suspect that millions of stars in the enormous galaxy have families of orbiting planets. But a space ship from earth would take two million years to get there, even it it traveled at almost the speed of light.