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STEX

retired
Technology DemonstrationLEOCOSPAR 1998-055ALaunched 10/3/1998
Admin Edit
Mission & Launch
Launch Mission
STEX/USA 141
Launch Vehicle
ARPA Taurus
Launch Date
10/3/1998
Last Contact
6/22/1999
Orbit & Mass
Orbit Class
LEO
Altitude
706 km
Inclination
84.99 deg
Dry Mass
510 kg
Total Mass
671 kg
Payload Classification
Mission Type
Technology Demonstration
Payload Category
TECH
Payload Class
D
Organizations
Operator
U.S. National Reconnaissance Office (NRO)
Manufacturer
Lockheed Martin
Registry
COSPAR ID
1998-055A
UN Registration
ST/SG/SER.E/353
Track
Mentions
1
All verified mentions of this spacecraft in source documents.
0.0-5.0
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The SoftRide vibration mitigation ring was tested on the Naval Research Lab's GEOSAT Follow-On satellite and the NRO’s STEX satellite in 1998.

PlanCapabilityValue 3.5Apr 21, 2025Anything but expendable (part 3)