ITOS (Improved TIROS Operating System)

ITOS (Improved TIROS Operating System) is a series of American weather satellites, launched between 1970 and 1976, which followed on from the TIROS series. ITOS-1 was also known as TIROS M but later spacecraft in the series were given NOAA (National Oceanic and Atmospheric Administration) designations after NOAA took over the management of the program from ESSA (Environmental Science Services Administration).