One of the most stunning images ever take of Saturn by the Cassini space probe – the planet backlit by the distant Sun, with the normally faint E ring glowing in a blue halo of light.
At the kick off for the new Merkinch Nature Reserve astronomy programme tonight, I got to talk about one of my favourite planets of all time – Saturn and its mind blowing ring system.
The dynamics of the rings are so subtle and complex. Some of the gaps in the rings are made by moonlets clearing paths, whilst other moons are actually replenishing the rings.
The small moon Enceladus is a fascinating example. It’s spewing out frozen ice from its south pole due to tidal heating, effectively generating Saturn’s faint E ring (the faint blue outer ring pictured above).
Enceladus, a small icy Moon with a salty internal ocean. Tidal stresses imparted by Saturn produce great jets of water from the southern pole of Enceladus, which instantly freeze, adding icy material to Saturn’s E ring.
You could sit on a moonlet of Saturn and watch the rings forming little wavelets in real time around you. Some of the larger rings actually wash back and forth like waves on a giant ocean.
Many of the smaller moonless orbiting Saturn have a polished or smooth aspect to them. This is due to fine particulates from the rings being drawn towards them due to gravity, effectively power coating the surface and covering over any craters or blemishes. This accretion of material onto the moons has been imaged by Cassini.
We had great turnout for the kickoff. The next event is a Moon special on Nov 7th. Look out for eventbrite links here on on my Facebook page.
The tiny moon Pan, clearing a path through Saturn’s rings. Its gravity is strong enough to produce beautiful ripples within the rings. As it orbits, Pan receives a fine power coating of frozen dust from the rings lending the moonlet a smooth, polished appearance.
