|A cloud of cold, charged gas around Earth, called the plasmasphere and seen here in purple, interacts with the particles in Earth’s radiation belts — shown in grey— to create an impenetrable barrier that blocks the fastest electrons from moving in closer to our planet. These findings were published in Nature magazine on Nov. 26, 2014. Image by NASA/Goddard|
Excerpt from pbs.org
A team led by professors and scientists from the University of Colorado at Boulder have discovered an invisible shield in space that blocks Earth from so-called “killer electrons,” according to findings published in Nature on Thursday.
“Somewhat like the shields created by force fields on Star Trek that were used to repel alien weapons, we are seeing an invisible shield blocking these electrons,” said Professor Daniel N. Baker, the lead author of the study in a press release.
“It’s an extremely puzzling phenomenon.”
According to NASA, “killer electrons” are the devilish doppelgangers of Earth’s subatomic allies.
While the flow of electrons is used as electricity to power everything from cell phones to light bulbs, when electrons reach high speeds like that of more than 100,000 miles per second in space, they can become dangerous and have been known to destroy satellites and even injure astronauts.
The shield, said to be located some 7,200 miles from Earth and impenetrable, lies within the Van Allen radiation belts, two rings around Earth containing potent electrons and protons trapped by the Earth’s magnetic field.
In 2008, NASA’s STEREO spacecraft, discovered that electrons turn into speedy, destructive “killer electrons” in part when picked up in the Belts by powerful radio waves known as whistlers.
Luckily though: “It’s almost like theses electrons are running into a glass wall in space,” said Baker of the shield, which was discovered using data collected by NASA’s Van Allen probes.