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Explorer 11

An artist's impression of the Explorer 11 satellite in flight. (Credit: NASA)
Lifetime: April 1961 - November 1961
Portion(s) of spectrum studied: gamma ray
Country (primary): United States
Primary Science
Explorer 11 was the first space-bourne gamma-ray telescope.
Science Highlights
- Detection of 22 gamma-ray events.
Instruments
- Gamma-ray detector sensitive to gamma rays with energy above 50 MeV