A planetarium software that shows a 3D simulation of the night sky
Stellarium renders 3D photo-realistic skies in real time with OpenGL. It displays stars, constellations, planets, nebulae and others things like ground, landscape, atmosphere, etc.
Real-time 3D visualization of space
Celestia is an application for real-time 3D visualization of space, with a detailed model of the solar system, over 100,000 stars, more than 10,000 galaxies, and an extension mechanism for adding more objects.
ChronosXP is a planetary hours astrology program for Windows. It runs from the system tray where it displays a glyph corresponding to the current planetary hour. Planetary hours/days can also be viewed for any given time or location.
Java based astronomical logging software which stores it's data in a free and open XML based format (OpenAstronomyLog).
Java version of Stellarium.