once i open it from my desktop i cant find out how to close or exit it ??? help
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Please don't fill out this field.
Move the mouse to the lower edge and the menu should appear. The last icon on the right is the exit button
Or simply press Ctrl+Q
Unless it is 'full screen' (key F11), there are also the usual Windows controls at the top right hand corner.
Well, Stellarium launches in full-screen by default, so...