Proton Series
The Proton 4 satellite. (Credit: Soviet Space Program)
The Proton series of satellites were launched by the Soviet Union in the 1960s to study very high energy cosmic rays.
Lifetime: July 1965 (first launch, Proton-1) - July 1969 (last satellite, Proton-4, reenters atmosphere)
Portion(s) of spectrum studied: gamma-ray
Country (primary): Soviet Union
Primary Science
Instruments
Links to more information
Proton 1
Lifetime: July 1965 - October 1965
Science Highlights
- Measured the intensity and energy spectrum of cosmic gamma-rays over 50 MeV
Proton 2
Lifetime: November 1965 - February 1966
Science Highlights
- Measured the intensity and energy spectrum of cosmic gamma-rays over 50 MeV
Proton 4
Lifetime: November 1968 - July 1969
Science Highlights
- Measured the intensity and energy spectrum of cosmic gamma-rays over 50 MeV