NASA’s Van Allen Probes Discover a Surprise Circling Earth
Two giant swaths of radiation, known as the Van Allen Belts, surrounding Earth were discovered in 1958. In 2012, observations from the Van Allen Probes showed that a third belt can sometimes appear. The radiation is shown here in yellow, with green representing the spaces between the belts.
Credit: NASA/Van Allen Probes/Goddard Space Flight Center