Exoplanet Explorer 3D!

Celestia is a free real-time 3D space simulation, allowing unrestricted access to hundreds of thousands of stars.

Gaia Sky is a real-time, 3D, astronomy visualisation software that runs on Windows, Linux and OS X. It is developed in the framework of ESA's Gaia mission to chart about 1 billion stars of our Galaxy in the Gaia group of the Astronomisches Rechen-Institut (ZAH, Universität Heidelberg).

3D simulation of the Solar System and night sky - real time virtual orrery and observatory

Stellarium Mobile is a fully-featured planetarium for your phone. It shows a realistic night sky map in 3D, just like what you see with the naked eye, binoculars or a telescope.

SourceForge presents the Solar Model project. Solar Model is an open source application. SourceForge provides the world's largest selection of Open Source Software. The Solar Model is real time modeling of solar system. It allows user to navigate in space, to control time counting (speed-up time flow) and estimate movement of space bodies, bind camera to space objects (for example, from Moon on Earth in real time).