FISL CIN 42, 17/0 
ITOS (Improved TIROS Operational System) 
Individual satellites in the ITOS system have been called NOAA since the formation 
of the National Oceanic and Atmospheric Administration. 
  
. Launch date Ended operation Significance i 
ITOS-1 (NASA's January 1970 June 1971 . Prototype ín second generation 
TIROS-M) polar-orbiting system 
NOAA-1 December 1970 August 1971 First NOAA funded operational 
; satellite 
NOAA-2 October 1972 January 1975 Carried all scanning radiometers 
NOAA-3 November 1973 August 1976 Direct transmission of VTPR data 
NOAA-4 November 1974 
NOAA-5 July 1976 . Primary operational polar-orbiting 
satellite, backed up by NOAA-4 
ORBIT: Sun-synchronous, near polar Inclination: 102° 
Altitude: 1470 km (average) Orbits per day: 12.4 
Period: 115 minutes 
SENSORS: 
ITOS-1 and NOAA-1: 
Advanced Vidicon Camera System (AVCS) Automatic Picture Transmission (APT) 
s2-channel Scanning Radiometer (SR) Flat Plate Radiometer (FPR) 
Solar Proton Monitor (SPM) 
NOAA-2 to 5: Wavelength (um) Resolution Measurement 
Very High Resolution 0.60-0.70 lia cloud top temperatures 
Radiometer (VHRR) : 10.5-12.5 ground and sea surface 
temperatures day/night 
Scanning radiometer 0.40-1.1 4,2 and same as VHRR but lower 
10.5-12.5 8 km resolution 
Vertical Temperature 15 (6 channels) i vertical temperature 
Profile Radiometer 12 (1 channel) profiles of atmosphere, 
(VTPR) 19 (1 channel) amount of cloud cover 
day and night 
Solar Proton Monitor solar proton flux, to 
estinate degree of 
: sun's activity 
PURPOSE: Observe, describe, and predict state of oceans, atmosphere, and sun 
Global coverage twice daily of cloud patterns, surface temperatures, 
temperature profiles from surface to 30 km, and solar proton levels 
Determine size and shape of Earth 
GROUND STATIONS: Command and Data Acquisition (CDA) stations at Wallops, Va., 
and Gilmore Creek, Alaska 
SR - Taped data received at CDA's; also direct readout to suitably equipped 
stations within radio range of satellite 
VHRR - Primarily direct readout to S-Band receivers at CDA's and Redwood City, Calif. 
Onboard storage for 8 minutes of data per orbit 
VTPR - Transmitted to CDA's; processed at NESS, Suitland, Md. 
SPM - Relayed from NESS to Space Environment. Labcratory in Boulder, Colorado. 
' DATA AVAILABILITY: National Environmental Satellite Service (NESS) 
World Weather Building, Camp Springs, Md. 20031 
SR and VHRR imagery, visible and infrared, as well as many special product 
such as mosaics, SST maps, ice analyses. : 
FOR MORE INFORMATION: The Operation of the NOAA Polar Satellite System, by 
: J. J. Fortuna and L. N. Hambrick 
NOAA Technical Memorandum NESS 60 
NOAA/NESS Office of Systems Integration 
Washington, D. C.