Significant strides have been made in free Desktop Planetarium software for modern commercial computers. Applications range from the simple to the complex. Many of these astronomy applications can run on several computer platforms.
There is a wide selection of free astronomy software available to an equally wide audience. While several applications provide excellent all-in-one solutions to meet most astronomers’ needs, other tools feature narrow but focused functionality. Young students and novice astronomers may want to begin with MHX Astronomy Helper, Solar System 3D Simulator or Asynx Planetarium. The next step up from these starter applications includes DeskNite and Deepsky Free, tools aimed at more advanced users. The best overall experience may be found in Celestia, Stellarium and Microsoft’s WorldWide. Integration between the sky surveys and the Hubble Telescope that make Sky in Google Earth a valuable educational tool. Digital Universe Atlas has the opportunity to view objects in different types of electromagnetic radiation, ranging from radio to infrared radiation, visible light and gamma rays.
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I also use free software Cartes du Ciel (Sky Charts). It is easy to use and very usefull for planing of your observation session.
You can also get software for your mobile phone. “Star Walk” for the iPhone. “Pocket Stars” for Windows devices.
Thanks for the list of the planetarium softwares. They’ve very useful and full of excellent functions.