Lisa Federhar, age 10, of Tucson, Arizona, for her question:

How are moons, planets and stars different?

The sky is populated with assorted heavenly bodies, and every young space ager knows that among them are planets, stars and moons. We should know which is which, but even people who should know better make mistakes. When we look up in the sky we can see only one moon. It is, of course, the one where the famous Eagle spacecraft landed, taking the first humans to another world. The moon is a moon because it orbits around and around the planet earth. Through a small telescope you can spot four moons orbiting the giant planet Jupiter.

A planet orbits around a star, as the earth and the other eight planets orbit our starry sun. A star is an enormous atomic bonfire,, blazing with nuclear energy. The light from the seething stars reach us from many millions of miles away. A star is a star because it is a huge seething furnace. Neither planets nor moons are on fire. A planet orbits a starry sun, while a moon orbits a planet and the two of them spin together around the sun