The Landsat 7 satellite system was designed to operate in a manner that will substantially advance the application of remote land observations to global change research. The Enhanced Thematic Mapper- Plus (ETM+) sensor aboard the spacecraft currently acquires multispectral digital image data of the Earth’s land surfaces on a routine basis. The quality of the ETM+ data is excellent, meeting or improving upon pre-launch specifications. The data are transmitted to a globally distributed set of ground stations including the primary U.S. ground station at the U.S. Geological Survey EROS Data Center in Sioux Falls, South Dakota. The U.S. Government manages the Landsat 7 satellite system A major program objective is to create an ETM+ data archive at the EROS Data Center that provides global coverage of the Earth’s continental and coastal surfaces on a seasonal basis. These data are available on a non-discriminatory basis at the incremental cost of fulfilling a user request. Once purchased from the EROS Data Center, no restrictions are placed on subsequent distribution of the data. This strategy fosters the operational applications of ETM+ data while advancing studies of the Earth as a system.
James R. Irons,
"Present and future of the Landsat program", Proc. SPIE 4049, Algorithms for Multispectral, Hyperspectral, and Ultraspectral Imagery VI, (23 August 2000); doi: 10.1117/12.410333; https://doi.org/10.1117/12.410333