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...

Ricky Leon Murphy decided to create this website when he was working towards a master’s degree in astronomy, and he still keeps it updated regularly, along with the assistance of his wife, Chanthirar. The site has been the recipient of several awards over the past few years, and visitors looking for basic and accessible information about the world of astronomy will not be disappointed. Near the...

At this Web site, the Hawaiian Astronomical Society provides users with educational information for over seventy constellations. First, visitors can read the amusing myths associated with each constellation. Following, students will find interactive, wide view and binocular width maps depicting the locations of the constellations, stars and deep sky objects. Everyone can enjoy the many remarkable...

This site from Jim Kaler, a Professor of Astronomy at the University of Illinois, is geared toward amateur and budding astronomers. Kaler offers detailed but non-technical descriptions of selected stars and a link to a photo of their respective constellations. Another section of the site, The Natures of Stars, consists of basic overviews of key concepts. The star descriptions are interesting to...

The Virtual Sky Viewer is sponsored by The Center for Advanced Computing Research at the California Institute of Technology and the Microsoft Corporation. The Web site allows users to view "stunning, seamless images of the night sky; not just an album of popular places, but the entire northern sky at high resolution". Although reading the help link before attempting to use the viewer is recommend,...