Space Exploration Timeline

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OSO 5 telescope

Jan 22, 1969 – Apr 2, 1984

Measured diffuse background X-ray radiation from 14-200 keV.

https://en.wikipedia.org/wiki/Orbiting_Solar_Observatory

Includes events (2):
Jan 22, 1969
Launch of OSO 5 (OSO F)
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Apr 2, 1984
Re-entry date of OSO 5 (OSO F)
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