Online and Interactive Astronomy Links

• Celestial Sphere - The web's best online virtual planetarium.
• AstroViewer - Dirk Matussek's really well done planetarium applet with 1400 stars. Nice user interface. Can generate printable charts (pdf format too.)
• Sky View Cafe - Another virtual planetarium with planetary orbits and ephemeris, calendar, and Jovian/Saturn moons. Easily jump to a number of celestial events.
• Sky & Telescope Interactive Sky Chart - A cool planetarium applet from Sky and Telescope magazine. Can generate printable sky charts.
• Stars and Constellations - Information and views of the constellations. Includes interactive star charts.
• Fourmilab - John Walkers's collection of online software including Earth and Moon Viewer, Solar System Live and Your Sky.
• GeoAstro Applet Collection - Juergen Giesen's collection of small astronomy applets.
• Night Sky Observer - Lots of astronomy news.
• Star Journey: The Heavens - Star Chart @ nationalgeographic.com
• SEDS - Home of Nine Planets Solar System Tour, Messier Deep-Sky Catalog, and various other gems.
• Skyview - NASA's virtual telescope.
• Heavens Above - Satellite and star observation maps.
• Virtual Solar System - Virtual reality tour of the solar system from National Geographic.
• Solar System Simulator - Generate pictures of solar system bodies from many different viewpoints. From NASA/JPL/Caltech.
• Orbiter - A visually stunning and realistic spacecraft simulator for Windows.