Stellarium is free GPL software which renders realistic skies in real time with openGL. With Stellarium, you really see what you can see with your eyes, binoculars or a small telescope. Stellarium is also used in real planetariums.
Stellarium Open Source 3D Planetarium
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| From Linux and Lamp – Open Source Software |
Works with Linux, Mac OSX and Windows. There is also one that you can carry along with you – Stellarium at PortableApps
Celestia – The free space simulation The free space simulation that lets you explore our universe in three dimensions. Celestia runs on Windows, Linux, and Mac OS X. Unlike most planetarium software, Celestia doesn’t confine you to the surface of the Earth. You can travel throughout the solar system, to any of over 100,000 stars, [...]
A Multimedia Tour of the Solar System by Bill Arnett. The Nine Planets Solar System Tour This website is an overview of the history, mythology, and current scientific knowledge of the planets, moons and other objects in our solar system. Each page has my text and NASA‘s images, some have sounds and movies, most provide [...]
Astronomy Telescope Making – Willie Koorts Computerised Satellite Tracking – control a telescope for Tracking Satellites. Turn your PC into a 1000-lap-memory logged stopwatch & set its RTC by radio. General positional astronomy program with real-time Alt/Az output. Here are fully illustrated pages of the re-building of my 9″ Newtonian Telescope.