The USGS EROS archive contains a large number of Landsat scenes. While many scenes collected worldwide are available from the USGS EROS archive, each ground station in the International Cooperator (IC) network is currently the primary source for distributing the captured data in their area.
Data not found in the USGS archive may be available from the ground station that collected the data. The International Ground Station Network Web page displays contact information and coverage maps.
There have been data exchanges between the USGS and some ICs, and the Landsat Global Archive Consolidation (LGAC) effort is underway. These scenes are copied into the USGS Landsat archive and made available for searching and downloading from EarthExplorer, GloVis, and the LandsatLook Viewer.