Dating Saturn's Rings

A new study suggests Saturn's legendary rings formed shortly after the planet itself.  Researchers used data from the Cassini spacecraft to determine the amount of dust in the rings, which are mostly water ice.  By comparing that amount with the rate dust would have arrived in the area, they determined the rings cannot be a recent development, as some argue.

In fact, they set the age of the rings at about 4.4 billion (Earth) years.  They also say the rings include interstellar dust, which is intriguing in its own right.