Probes Reveal Previously Undetected Radiation Belt Around Earth

NASA's Van Allen Probes were launched in August 2012 to study the Van Allen belts - gigantic radiation belts surrounding Earth, which can swell dramatically in response to incoming energy from the sun, engulfing satellites and spacecraft and creating potential threats to manned space flight. Within days of launch, the probes revealed a third ring of radiation that persisted for about a month.