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Discoverer 21

retired

Earth ObservationLEOCOSPAR 1961 ZETLaunched 2/18/1961

Mission & Launch

Launch Mission: Discoverer 21
Launch Vehicle: Thor Agena B
Launch Date: 2/18/1961
Last Contact: 2/20/1961

Orbit & Mass

Orbit Class: LEO
Altitude: 634.5 km
Inclination: 80.74 deg
Dry Mass: 146 kg
Total Mass: 936 kg

Payload Classification

Mission Type: Earth Observation
Payload Category: IMG
Payload Class: D

Organizations

Operator: U.S. Air Force
Manufacturer: Lockheed Martin

Registry

COSPAR ID: 1961 ZET
UN Registration: A/AC.105/INF.001