EROS Reflector The USAF's Project EROS (Experimental Reflector Orbital Shot) was the first USAF solar reflector experiment in space. Its purpose was to find out if reflectors could be used for collecting and concentrating the sun's heat to generate electricity in space solar power systems. The USAF completed the first orbital tests in 1963. The Fresnel type reflector on display at the museum is similar to one that was attached to an Agena upper stage vehicle and launched with a Discoverer satellite. The reflector was folded for launch and then opened when the Agena achieved orbit. It stayed with the Agena throughout the experiment and did not return to earth with the Discoverer. Although conversion of the sun's energy was not attempted, the experimental data radioed back to earth showed that the reflector could produce an intense concentration of the sun's heat in a small area. At the end of the small arm extending in front of the reflector is a radiometer that measures the intensity of the solar energy striking it. The reflector was developed by the Research & Technology Division of the Aero Propulsion Laboratory, Aeronautical Systems Division, Wright-Patterson Air Force Base, Ohio. It was built by the Allison Division of General Motors Corp. Click here to return to the Missile Gallery. Find Out More Related Fact Sheets Thor Agena A Note: The appearance of hyperlinks does not constitute endorsement by the National Museum of the USAF, the U.S. Air Force, or the Department of Defense, of the external website, or the information, products or services contained therein.