Stellarium

Licence: Free
Developer : The Stellarium Project
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Open source desktop planetarium.

DESCRIPTION
Stellarium is an open source desktop planetarium. It renders the skies in realtime using OpenGL, which means the skies will look exactly like what you see with your eyes, binoculars, or a small telescope. Stellarium is very simple to use, which is one of its biggest advantages: it can easily be used by beginners.

Stellarium renders 3D photo-realistic skies in real time with OpenGL. It displays stars, constellations, planets, nebulas and others things like ground, landscape, atmosphere, etc.