Prospero

Also called X3

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General

Designation	05580 / 71093A
Launch date	28 Oct 1971
Country of origin	United Kingdom
Mission	Technology experimentation
Perigee/Apogee	531/1402 km
Inclination	82°
Period	104.4 min
Launch vehicle	Black Arrow #4

Designed and operated by the RAE. Only satellite launched by a British rocket. Tested solar cells.

In 2011, a team of British scientists want to resume communication with it.

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End of life

Out of service

1973

Technical data

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Specifications

Prime contractor
Platform
Mass at launch	86 kg
Mass in orbit
Dimension	11 m diameter
Solar array
Stabilization	spin stabilized, 4 rpm
DC power
Design lifetime

Transmits on 137.56 MHz (was still heard in 2000, switched on around anniversary date only)

Carried an onboard tape recorder which failed after 730 replays on 24 May 1973.

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