THEMIS missions tagged posts

In a background magnetic field, represented by the cyan arrows, two electrons are propagating to the right, executing identical gyromotion. A circularly polarized electromagnetic wave approaches the upper electron from the left.
Credits: NASA

Encircling Earth are two enormous rings – Van Allen radiation belts – of highly energized ions and electrons. Various processes can accelerate these particles to relativistic speeds, which endanger spacecraft unlucky enough to enter these giant bands of damaging radiation. Scientists had previously identified certain factors that might cause particles in the belts to become highly energized, but they had not known which cause dominates.

Now, with new research from NASA’s Van Allen Probes and Time History of Events and Macroscale Interactions during Sub...