Land·sat (lānd'sāt') n. Any of various satellites operated by U.S. government organizations, used to gather data for constructing images of the Earth's surface.
Landsat (lānd'sāt') Pronunciation Key
Any of various satellites used to gather data for images of the Earth's land surface and coastal regions. These satellites are equipped with sensors that respond to Earth-reflected sunlight and infrared radiation. The first Landsat satellite was launched in 1972. Currently, the seventh satellite (Landsat 7) is orbiting Earth.