Prowler (satellite)

The government of the United States has never acknowledged its existence, however it has been identified by amateur observers and through leaked information.

It had a mass of around 1,300 kilograms (2,900 lb) and carried modifications to reduce its visibility to ground-based observers and to radar.

Its purpose was either to monitor them and return data about them,[4] or to perform a signals intelligence mission such as intercepting communications between those satellites and the ground.

[6] Prowler was deployed from Atlantis at around 04:37 UTC on 17 November 1990, and boosted into geosynchronous transfer orbit by a PAM-D upper stage.

[8] The object was subsequently lost, then was rediscovered in June 2000 when its flashes became brighter,[9][10] some even visible with the naked eye.