The NASA-USGS Landsat program provides the longest continuous space-based record of Earth’s land. Landsat satellites provide essential information about land surfaces to help scientists detect and monitor melting glaciers, urban growth, natural disasters such as floods and droughts, as well as changes in farms and forests. This information is useful to land managers and policy makers who make decisions about our resources and our environment.
Currently, there are two Landsat satellites in space. Both are flying over the Earth at the altitude of 438 miles (705 km):