Right-click (using a PC) or Option-click (using a Mac) on the image to save the file:
Although this image may look small it has only been scaled to fit on this web page. It actually has all the resolution needed for a full-size print.
Once the entire image has loaded on your screen, right-click (using a PC) or Option-click (using a Mac) on the image. You will get a list of options. Depending on which browser you use (Internet Explorer, Firefox, Opera, etc.) one of those options will say something like: "Save Image As," "Save Picture As," or "Save Target As." Choose that.
A dialog will appear asking where you want to save the image. Pick a spot on your computer (Desktop, My Documents, Home, etc.) and click "Save." Congratulations – you are now the proud owner of a digital Hubble image. Remember where you put the image, because you'll have to find it later.