Complex sentence: During the first approximately 100 days, LDCM will undergo on-orbit checkout and verification by NASA and once complete LDCM will be handed over to the USGS and officially be renamed Landsat 8.
Split into simpler sentences: During the first approximately 100 days in orbit, LDCM will undergo checkout and verification by NASA. Once complete, LDCM will be handed over to the USGS and officially renamed Landsat 8.