Source: USGS
On Friday, December 18, 2009, the transmitter on Landsat 5 experienced technical difficulties. There has been no Landsat 5 data acquired since that time. The U.S. Geological Survey Flight Operations team has extensive experience with this transmitter and is currently addressing the situation. Any news or updates will be posted on the USGS Landsat website.

Above the Earth, Below the Surface: Landsat’s Role in Monitoring Water Quality
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.