Here are a few additional NASA imagery Web sites that you may find helpful:

Gateway to Astronaut Photography of Earth- https://eol.jsc.nasa.gov/SearchPhotos
The entire collection of catalog records for photos of Earth taken during manned spaceflight missions. Continuously updated.

NASA Human Space Flight Web, Multimedia Gallery - https://spaceflight.nasa.gov/gallery
Press release photos from shuttle missions since STS-82, press release photos from the space station, and video, audio, and animation files from the shuttle and space station programs. Also contains some pre-shuttle multimedia. All new press release photos and other multimedia are published here. Low and high resolution imagery. Continuously updated.

KSC Shuttle Photo and Video Archive - https://science.ksc.nasa.gov/shuttle/photos
Preflight, launch, and landing photos and videos from shuttle missions since STS-67. Low and high resolution images available. Continuously updated.

GReat Images in NASA (GRiN) - https://grin.hq.nasa.gov
Over 1000 NASA images of historical interest. Images available in low, high, and very high resolutions - suitable for publishers and the media. Frequently updated.