Astronomy Picture of the Day (APOD)
Their archive contains the largest collection of annotated astronomical images on the internet. An APOD Facebook page is maintained by fans of the site.
Produced by NASA's Earth Science Division, EOS Project Science Office and the Universities Space Research Association, EPOD provides and archives a photo, image, graphic or artwork a day to highlight Earth phenomena.
A great many resources by NASA for educators, this site includes and A-Z list for both NASA Websites for Education, as well as NASA Educational Publications.
NASA JPL Mars Exploration Rover Mission
This collection contains separately organized sites with educational information for children, students and educators as well as videos, photos and more from missions of NASA's Mars Rovers and thoughts on future robotic exploration.
NASA’s Planetary Image Archive (PIA) contains images organized by planet on the front page. Users may also search spacecraft and technology, animations or download a Space Images App.
