NASA's THEMIS: 'singing' electrons help create and destroy 'killer' electrons

		IMAGE: This is an artist's concept of the THEMIS main orbits, represented by red ovals. Blue lines represent Earth's magnetic field over the night side. The white flash represents energy released... Click here for more information.

GREENBELT, Md. -- Scientists using NASA's fleet of THEMIS spacecraft have discovered how radio waves produced by electrons injected into Earth's near-space environment both generate and remove high-speed "killer" electrons.