Yggdrasil...

The rings of Saturn take center stage in this portrait by the Hubble Space Telescope taken on June 20, 2019. Credit: NASA, ESA, A. Simon (GSFC), M.H. Wong (University of California, Berkeley) and the OPAL Team

Topics: Astronomy, Planetary Science, Space Exploration

There was a strong temptation to use the Norse legend of Bifrost - the rainbow bridge made popular in Thor, but rings of trees tell their age, so...

Yggdrasil is the tree of life, and it is an eternal green Ash tree; the branches stretch out over all of the nine worlds in Norse mythology, and extend up and above the heavens. Norse mythology: Yggdrasil.

Against earlier studies estimating an age of just 100 million years, new research suggests the planet’s rings could be as old as the solar system itself.

The great Saturn ring debate is far from settled, a new study suggests.

For years, scientists have argued about the age of Saturn’s famous rings: Are they ancient, dating to the birth of the planet itself? Or did the ring system form more recently, in just the past hundred million years or so?

This latter hypothesis has been gaining steam in the last few years, with multiple papers reporting that the rings could be even younger than the dinosaurs. Such studies cite the rings’ composition—more than 95% pure water ice—and total mass, which NASA’s Cassini mission pegged at about 15.4 million billion metric tons shortly after the probe’s epic “grand finale” at Saturn in 2017. (For perspective, 15.4 million billion metric tons is about 40% the mass of the Saturn moon Mimas, which is 250 miles, or 400 kilometers, wide.)

Saturn’s Rings May Be Ancient After All, Mike Wall, Space.com and Scientific American