Saturn's Ring Is The Biggest in Solar System, Made Up of Mainly Small Dust Particles, Study Finds

Saturn's ring is the biggest in solar system, according to researchers. The ring was first discovered in 2009.

In a study, researchers concluded that the faint ring known as the Phoebe ring is 270 times the size of Saturn and over 10 times larger that Saturn's E ring, which is the second largest ring in the solar system.

"For the first time ever, we have the ring image in its entirety," said University of Maryland's Douglas Hamilton, who along with University of Virginia's Michael Skrutskie and CalTech's Anne Verbiscer discovered the ring. CalTech's Frank Masci contributed to the latest Nature paper.

"We know how big this ring is now and we didn't before," he said. "The outer edge is starting to give us interesting information about what is happening inside the ring, the forces and processes that make it function."

Researchers analyzed images from NASA's WISE spacecraft and found that the planet's outermost ring is made mostly of small dust particles of around 10 microns in size or one-fifth the width of a human hair.

"I constructed theoretical models for how the dust particles of different sizes would move and then I constructed artificial rings. What would the ring look like if it were made only of large particles? What would it look like with only small particles? What about a mixture?" he said. "The data is good enough to constrain those models so we rule out the possibility of the ring being composed entirely of large particles. The smallest ones seem to be responsible for something like 90 percent of the light or more."

The study was published in the journal Nature.