Cassini Finds Radiation Between Saturn and Innermost Ring (need new theory

[papau]

http://www.latimes.com/news/nationworld/nation/la-sci-cassini6aug06,1,5851464.story?coll=la-headlines-nation

Cassini Finds Radiation Between Saturn and Innermost Ring (need new theory)

By Thomas H. Maugh II, Times Staff Writer

NASA's Cassini spacecraft has found a new radiation belt around Saturn, inside the orbit of the rings where scientists thought such a belt couldn't exist.

Data from the craft released Thursday also showed that the prevalence of storms on the planet's surface was lower than it was when Saturn was visited by Voyager 2 two decades ago, possibly because of changes in the shadow cast by the planet's rings.

The discovery of the radiation belt was "a huge surprise," said Donald G. Mitchell of Johns Hopkins University, who is in charge of the on-board magnetospheric imaging device that identified the belt.

Previous Saturn missions had shown the presence of strong radiation belts — essentially ring-shaped concentrations of ionized particles — outside the orbit of the rings. Researchers had thought, however, that the rings would absorb any particles that tried to get closer to the planet.<snip>

Mitchell speculated that the radiation belt was produced by electrically neutral particles that originated beyond the orbit of the rings and were dispersed in all directions. Some make their way through the rings and emerge close to Saturn, where they are stripped of an electron by the planet's magnetic field, forming the radiation belt. <snip>