Turn your computer into a virtual telescope. Microsoft's WorldWide Telescope brings together imagery from the best ground and space-based telescopes for a seamless exploration of the universe. Also offers guided tours of the sky by astronomers and educators.
Sky View Cafe 3.0
Java applet that lets you use your web browser to see many types of astronomical information, in both graphical and numerical form.
Google Earth: Sky
Information about Google Earth's Sky feature, which allows users to zoom in to distant galaxies and nebulae and view constellations and the movements of the planets.
Ultimate Messier Object Log, The
Freeware database that contains relevant information for all 110 Messier Objects and various layouts to assist amateur astronomers in documenting their search for deep sky objects.
Cross-platform Java program and browser applet which displays a Mars "sunclock", a graphical representation of Mars showing the current sun- and night-sides of Mars.
STD Aurora Monitor
Software for monitoring auroral activity and space weather that allows user to stay informed about conditions via their computer, cell phone, or pager.