Exploded view of the first successful U.S. satellite, Explorer I, showing the instruments inside. Explorer I was launched January 31, 1958 and discovered the radiation belts that surround Earth.
Exploded view of the first successful U.S. satellite, Explorer I, showing the instruments inside. Explorer I was launched January 31, 1958.
Explorer 1 contained experiments that turned our understanding of space upside down. To this day, scientists try to understand the dynamic, seething environment encircling Earth – known as the Van Allen radiation belts – that Explorer 1 helped discover.
Image Credit: NASA