Stellarium - Stellarium is a free open source planetarium for your computer.
Space Engine - Space Engine is a realistic virtual Universe you can explore on your computer.
Sky Guide - A window to the stars has never been more beautiful and easy to use.
OpenSpace - OpenSpace is open source interactive data visualization software designed to visualize the entire known universe and portray our ongoing efforts to investigate the cosmos.
SkyView - SkyView is powerful, easy-to-use app that answers questions about stars, constellations, and more.
Celestia - Real-time 3D visualization of space