[markbnine]

For planetary data, the PDS Imaging Node has pages both at NASA and the USGS. Here is the USGS page pointing to much of it: http://astrogeology.usgs.gov/facilities/cartography-and-imag.... The PDS formats can be difficult but tools like GDAL now deal with it. Here is tool I wrote to search much of it: http://pilot.wr.usgs.gov.