Celestia

Celestia is real-time 3D space simulation program which lets you travel through our solar system and to over 100,000 stars in our galaxy.Celestia is a free real-time space simulation that lets you experience our universe in three dimensions. 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, or even beyond the galaxy. All travel in Celestia is seamless; the exponential zoom feature lets you explore space across a huge range of scales, from galaxy clusters down to SpaceCraft only a few meters across. A `point-and-goto` interface makes it simple to navigate through the universe to the object you want to visit. The Navigation menu contains `Solar System Browser` and `Star Browser`options. The Solar System Browser displays a window with a tree view of allthe objects in the nearest solar system (if there is one within a light yearof your current position.). Clicking on the name of any object in the window will Select It. You can then use the Center or Go To buttons to display that object in the main Celestia window.