By Ron Cowen
FAJARDO, Puerto Rico — A newly discovered planetary ring can run circles around all the others. The gossamer band of dust encircles Saturn and has a measured diameter of about 24 million kilometers, or 200 times the diameter of the planet.
This finding makes the band the largest known planetary ring in the solar system, researchers reported October 6 at the annual meeting of the American Astronomical Society’s Division for Planetary Sciences. A billion Earths could fit inside the ring.
Calculations indicate the tenuous ring is probably even more extensive and is likely to have a diameter reaching 36 million kilometers.