WASHINGTON, Feb. 28 (Xinhua) -- The Van Allen Probes mission has discovered a previously unknown third radiation belt around Earth, U.S. space agency NASA announced Thursday.
Previous observations of Earth's Van Allen belts have long documented two distinct regions of trapped radiation surrounding our planet. Particle detection instruments aboard the twin Van Allen Probes, launched Aug. 30, revealed the existence of this new, transient radiation belt. Scientists observed the third belt for four weeks before a powerful interplanetary shock wave from the sun annihilated it.
The belts, named for their discoverer, James Van Allen, are critical regions for modern society, which is dependent on many space-based technologies. The Van Allen belts are affected by solar storms and space weather and can swell dramatically. When this occurs, they can pose dangers to communications and GPS satellites, as well as humans in space.
"The fantastic new capabilities and advances in technology in the Van Allen Probes have allowed scientists to see in unprecedented detail how the radiation belts are populated with charged particles and will provide insight on what causes them to change, and how these processes affect the upper reaches of Earth' s atmosphere," NASA's Associate Administrator for Science John Grunsfeld said in a statement.
The findings were also published online Thursday in the journal Science.