Stellarium can be used as an educational tool for teaching about the night sky or planning night sky watching and also it is being used in planetarium projectors.
How to download Stellarium
Visit Stellarium official web site and download the version that you want.http://stellarium.org
Minimal System requirements
Operating System :- Linux/Unix, Windows XP and above; OS X 10.7.4 and above3D graphics card which supports OpenGL 2.1
256 MiB RAM
150 MiB on disk
Features of Stellarium
Sky Default catalog of over 600,000 stars
Extra catalogues with more than 210 million stars
Asterisms and illustrations of the constellations
Constellations for 19 different cultures
Images of nebulae (full Messier catalogue)
Realistic Milky Way
Very realistic atmosphere, sunrise and sunset
The planets and their satellites
Interface
A powerful zoom
Time control
Multilingual interface
Fisheye projection for planetarium domes
Spherical mirror projection for your own low-cost dome
All new graphical interface and extensive keyboard control
Telescope control
Visualization
Equatorial and azimuth grids
Star twinkling
Shooting stars
Eclipse simulation
Supernovae simulation
Skinnable landscapes, now with spherical panorama projection