TIROS Operational System
Series of 9 satellites for operational meteorology, follow-on of the experimental TIROS series.
From a historical viewpoint, considered as the 2nd generation of NOAA polar orbiting satellites. Main improvements: operational adoption of the "cartwheel" configuration (as in TIROS-9), of the sunsynchronous orbit (as in TIROS-9 and TIROS-10) and of the real-time dissemination function (as in TIROS-8).
USA programme: ESSA, the predecessor of NOAA, responsible of the overall programme and the operations, NASA responsible of the development of the space segment.
Spin-stabilised satellites, with the spin axis perpendicular to the orbital plane ("cartwheel" configuration) and the cameras mounted on the side, activated when facing the earth.
Design lifetime 1 year.
Sunsynchronous orbits around 9:30 exploited, with two satellites at any time: ESSA 1, 3, 5, 7 and 9 equipped with instruments for stored data, ESSA 2, 4, 6 and 8 equipped for real-time transmission.
Replacement policy based on launching satellites of each series (odd-numbered or even-numbered) at yearly intervals.
See detailed description at
Selected data of odd-numbered satellites stored onboard and downlinked to the CDA (Command and Data Acquisition station) at Fairbanks.
Data from the even-numbered satellites downlinked in real time to APT receiving stations.
1966 - 1976
Associated satellites and instruments
Note: red tag => no longer operational , green tag => operational
, blue tag => planned