The best part: it's copyright free. You can download and use these images for whatever purpose you want, thanks to NASA's generous public images policy. 

NASA's image and video library.

NASA's image and video library.

"NASA Image and Video Library allows users to search, discover and download a treasure trove of more than 140,000 NASA images, videos and audio files from across the agency’s many missions in aeronautics, astrophysics, Earth science, human spaceflight, and more," NASA said in a press release Tuesday. "Users now can embed content in their own sites and choose from multiple resolutions to download." Read more...

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