Destructive electrons streaking into Earth's atmosphere

A unique study has been done of potentially destructive high-energy electrons streaking into Earth's atmosphere from space, employing two different and distant vantage points high above the Earth.

The researchers launched their project in Antarctica to record X-rays produced as falling electrons collide with the Earth's atmosphere.

"This is exciting for us because we are integrating data collected by our instruments with the data from NASA's Van Allen Probes," said Robyn Millan, an associate professor of physics and astronomy at Dartmouth College in New Hampshire.

This particle onslaught can lead to ozone depletion and damage to the orbital satellites that provide us with the navigation, communication, weather, and military-recognizance information.

These satellites fly through the Van Allen radiation belts -- giant concentric layers of charged particles held in place by the Earth's magnetic field.

An increase in particle density and charge brought about by solar activity can raise the level of threat to our critical satellites. Their findings appear in the journal Nature.

The team used instruments carried aloft by balloons launched from Antarctica, rising as high as 125,000 feet. The project called BARREL (Balloon Array for Radiation belt Relativistic Electron Losses) was supported by NASA.

The instruments recorded the X-rays produced as the falling electrons collide with the atmosphere.

"Our paper looked at plasma waves. These are like sound waves in air except that now you are in an ionized gas so the electric and magnetic fields are affected," Millan said.

"Those waves were causing the electrons to be scattered, yielding a new understanding of how the particles are getting kicked into the atmosphere. These same processes are probably happening throughout the universe and, with the tools at our disposal, we can study them in detail right here," Millan added.