#4708
Gaia Sky is a free, open-source and cross-platform (based on Java) 3D astronomy visualization software developed by ZAHUniversität Heidelberg from Germany. It is designed to map about 1 billion fixed stars in the Milky Way where our planet is located, based on the framework of ESA's Gaia mission, and supports VOTable, FITS, CSV and all formats supported by the STIL library.

#308
Stellarium is a free open-source desktop virtual planetarium software from France, supports Unix/Linux, Windows and Mac OS X platforms. It uses OpenGL to render the stars in real time, and generate a virtual 3D sky on your desktop, so the stars effect is almost completely the same as you observe the stars sky with only naked eye, telescope or astronomical telescope.