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Stellarium Astronomy Software: http://stellarium.org/en
Stellarium is a free open source planetarium for your computer.
It shows a realistic sky in 3D, just like what you see with the naked eye, binoculars or a telescope. It is being used in planetarium projectors. Just set your coordinates and go.
View screenshots: http://stellarium.org/en/screenshots.html
Wikipedia: https://en.wikipedia.org/wiki/Stellarium_(software)