Landsat 8, known before launch as LDCM, consist of two major segments: the observatory and the ground system. The observatory consists of the spacecraft bus and its payload of two Earth observing sensors, the Operational Land Imager (OLI) and the Thermal Infrared Sensor (TIRS). OLI and TIRS collect Landsat 8 science data. The two sensors coincidently collect multispectral digital images of the global land surface including coastal regions, polar ice, islands, and the continental areas. The spacecraft bus stores the OLI and TIRS data on an onboard solid-state recorder and then transmits the data to ground receiving stations.