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...

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...