September 15, 2009

Radiation belt found around a Saturn moon

NASA says its Cassini spacecraft's magnetospheric imaging instrument has detected a new, temporary radiation belt around the orbit of one of Saturn's moons.

Scientists located the new radiation belt in the orbit of the moon Dione, about 234,000 miles from the center of the planet.

The new belt, which has been named the Dione belt, was detected by the instrument for only a few weeks on three separate occasions in 2005, the space agency said in a statement. Scientists believe that newly formed charged particles in the Dione belt were gradually absorbed by Dione itself and another nearby moon, named Tethys, which lies slightly closer to Saturn at an orbit of 183,304 miles.

The discovery was presented Monday in Potsdam, Germany, during a meeting of the European Planetary Science Congress.

The Cassini-Huygens spacecraft is a joint operation of the U.S., European and Italian space agencies.