Fifty years ago today — October 27, 1962 — Explorer 15 was launched from Cape Canaveral on a Thor Delta rocket, to study a radiation belt produced three months earlier.
(The Starfish nuclear explosion, as seen from nearly 900 miles away in Honolulu, HI.
US Government image from Wikimedia Commons.)
Explorer 15 was instrumented with an array of radiation detectors, as its mission was to study the radiation belt produced by the Starfish nuclear test conducted on July 9, 1962. The Starfish test — conceived by the Atomic Energy Commission and what would become the Defense Nuclear Agency, and launched from Vandenberg AFB by the Air Force — revolutionized the understanding of electromagnetic pulse, but the energetic particles it created contributed to the failures of several low-earth-orbiting satellites.by