NASA's International Sun-Earth Explorer C (ISEE C) undergoing testing and evaluation inside Goddard's dynamic test chamber. Goddard engineers wear protective "clean room" clothing to prevent microscopic dust particles from damaging the sophisticated instrumentation. NASA launched the 16-sided polyhedron on 12 August 1978. From its halo orbit 932,000 miles (1.5 million kilometres) from Earth, the satellite monitored the characteristics of solar phenomena about one hour before its companion satellites - ISEE-A and ISEE-B - observed the same phenomena from a much closer near-Earth orbit. The correlated measurements supported the work of 117 scientists to obtain a better understanding of how the Sun controls Earth's near-space environment.
© National Aeronautics & Space Administration / Science & Society