Landsat is a joint effort of both USGS and NASA. USGS conducts Landsat operations and NASA develops and launches new satellites that meet USGS requirements. In addition to imagery of natural hazard events, Landsat provides valuable data for land use research.
Source: Jon Campbell, USGS
For further information:
+ USGS press release
Safeguarding freshwater resources is crucial, and while scientists use a variety of ground-based techniques to gauge water quality, the Landsat program has provided water quality data from orbit for decades.