Global spatial coverage is provided by the ERBE instruments on board the NOAA-9 and NOAA-10 satellites. Coverage between 60 degrees north and south latitude is provided by ERBS satellite. ERBS is a precessing satellite and produces the best diurnally sampled data because it sees all 24 hours of local time in 72 days. NOAA-9 and NOAA-10 are sun-syn satellite and do not cover the entire diurnal cycle, however they see the entire globe. NOAA-9 is the afternoon (2:30 PM LST) satellite and NOAA-10 is the morning (7:30 AM LST) satellite.