SeaWiFS Project http://seawifs.gsfc.nasa.gov/SEAWIFS.html
The purpose of the Sea-viewing Wide Field-of-view Sensor Project is to provide quantitative data on global ocean bio-optical properties to the Earth science community.
Earth System Science Online http://www.usra.edu/esse/essonline/
Universities Space Research Association OnLine Index. This site is maintained by the Cooperative University-based Program for Earth System Science Education (ESSE) with NASA support as part of the Division of Earth Sciences of the Universities Space Research Association (USRA).