ITOS
Improved TIROS Operational System

ITOS was the follow-on to the TIROS series of polar-orbiting US weather satellites, and marked the beginning of the use of the NOAA designator. The program was initially managed by the ESSA (Environmental Science Services Administration). NOAA later became the managing organization.

Spacecraft
3-axis stabilized. Two deployed solar panels. NiCd batteries.

Payload
AVCS (Advanced Vidicon Camera System). APT (Automatic Picture Transmission system). FPR (Flat Plate Radiometer). SPM (Solar Proton Monitor). VTPR (Vertical Temperature Profile Radiometer). VHRR (Very High Resolution Radiometer). ITOS-1, ITOS-A, ITOS-B carried AVCS, APT, FPR, SPM. ITOS-D, ITOS-E, ITOS-F, ITOS-G, ITOS-H carried FPR, SPM, VTPR, VHRR.

Country of Origin	United States
Customer/User	ESSA, NASA, GSFC, NOAA
Manufacturer(s)	RCA
Size	40 inch diameter, 48 inch height, 14 feet solar array span
Orbit	Typically around 1450 km x 1450 km, incl. = 101 deg

Launch Facts

Name	Int'l Desig.	Date	Site	Vehicle	Orbit	Mass(kg)
Notes
ITOS 1	1970-008A	1/23/70	WSMC	Delta N-6	LEO	309
Improved TIROS Operational Satellite
NOAA 1 (ITOS A)	1970-106A	12/11/70	WSMC	Delta N-6	LEO	306
Built for NASA; operated by NOAA
ITOS B	1971-091A	10/21/71	WSMC	Delta N-6	LEO	308
Unusable orbit
NOAA 2 (ITOS D)	1972-082A	10/15/72	WSMC	Delta 300	LEO	344
ITOS E	none	7/16/73	WSMC	Delta 300	FTO	345
Improved TIROS Operational System; 2nd stage failure
NOAA 3 (ITOS F)	1973-086A	11/6/73	WSMC	Delta 300	LEO	345
NOAA 4 (ITOS G)	1974-089A	11/15/74	WSMC	Delta 2310	LEO	340
NOAA 5 (ITOS H)	1976-077A	7/29/76	WSMC	Delta 2310	LEO	340