Compton Gamma-Ray Observatory
Lifetime: April 1991 - June 2000
Country (primary): United States
The Compton Gamma-Ray Observatory, or CGRO for short, was the second of NASA's great observatories. It was designed to study the gamma-ray sky over the energy range of 30 keV to 30 GeV.
- Discovered that gamma-ray bursts were distributed evenly over the whole sky
- Mapped the Milky Way using the 26-Aluminum gamma-ray line
- Discovered that blazars are the primary sources of the highest energy cosmic gamma-rays