Offered by the National Space Science Data Center of NASA, the Planetary Fact Sheets Web site contains helpful information for students studying astronomy. The site lists links to all of the planets, their satellites, and their rings, as well as to tables comparing all the planets. The planet pages contain a photograph and a simple list of dozens of facts such as mass, volume, distance to the...

The homepage of The Planetary Society, this Web site is devoted to planetary exploration and education. The site publicizes the latest meteor sightings around the world and other recent news. Educators and students can find lots of materials dealing with Mars including observing tips, events, and games. At the Learning Center, enjoyable activities from making comet balls to determining your weight...

Three planets that are larger than Jupiter have been found orbiting the star Upsilon Andromedae. Astronomers from four research institutions have confirmed this observation. This site provides information about the Upsilon Andromedae Planetary System.