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.
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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.