The earth's diameter is 12,756.3 km and its revolution period is 1 year. You probably knew the last fact, but most likely not the first. The Web site Absolutely Astronomy can provide this and a large amount of other facts about planets, moons, stars, constellations, messier objects, nebulas, and galaxies. Visitors can browse via the pull-down menus or search by a particular question. The basic...

Each day a new, beautiful image or picture of our intriguing atmosphere is presented on this Web site, created by NASA, along with a short description written by an expert. By selecting Discover the Cosmos, viewers can visit the archives, which features all the images presented since June 1995. In the Index, the images are also organized into the topics: Cosmos, Solar System, Space Technology, and...

Provided by the US Geological Survey Astrology Research Program, the Gazetteer of Planetary Nomenclature Web site contains nearly everything you ever wanted to know about naming the physical features of planets. The site provides a history of the activity, details how names are approved, and of course contains an exhaustive list. For example, did you know that an Apollo 16 astronaut named a...

The Hubble Space Telescope has returned an image of what is possibly the first planet outside our solar system. TMR-1C, about 450 light years away in the constellation Taurus, appears to have been "flung away from the vicinity of a newly forming pair of binary stars," as evidenced by a luminescent filament leading from the "planet" back to the stars. "Susan Terebey of the Extrasolar Research...

A collaboration between NASA's Planetary Data System Imaging Node, the Solar System Visualization Project, and the Jet Propulsion Lab's Media Relations Office, NASA's Planetary Photojournal offers user-friendly, continuously-updated access to approximately 2,000 images from various solar system exploration programs. Users can select from a number of spacecraft/ instruments for different images of...

Part of the Popular Topics section of the main NASA site, this collection of NASA resources is jam-packed with great photos, learning tools, announcements, and NASA agency news. Anyone interested in learning more about the solar system or the United States' efforts in space exploration (both manned and unmanned) will want to check out this great resource. In addition to the features on the main...

"December 4, 2000 -- In what ultimately may be their most significant discovery yet, Mars scientists say high-resolution pictures showing layers of sedimentary rock paint a portrait of ancient Mars that long ago may have featured numerous lakes and shallow seas." This exciting news comes from a recent NASA news article detailing the latest finds from the Mars Orbiter Camera on NASA's Mars Global...