Slashdot Mirror
'Ring Rain' Quenches Saturn's Atmosphere
astroengine writes "Saturn's rings rain charged water particles down onto the gas giant's atmosphere, causing measurable changes in the planet's ionosphere. This intriguing conclusion comes from astronomers using the W. M. Keck Observatory atop Mauna Kea in Hawaii that observed dark bands forming in Saturn's ionosphere. 'Saturn is the first planet to show significant interaction between its atmosphere and ring system,' said James O'Donoghue, postgraduate researcher at the University of Leicester and lead author of a paper to appear this week in the journal Nature. 'The main effect of ring rain is that it acts to 'quench' the ionosphere of Saturn, severely reducing the electron densities in regions in which it falls.'"
There are rings around Uranus.
I drank what? -- Socrates
To be honest, we really didn't expect to find it at any of the planets. It was proposed as a theory, with some evidence, at the time of Voyager, but has been relatively ignored since that time. Certainly, we would have looked for this effect at Saturn, if we'd thought it was a likely process, but in addition, the H3+ emission we measured in the paper is very weak. The first detection on the body of the planet was only last year, and it was only though the use of Keck, with its giant bucket-like collecting capabilities, that we were able to get a strong enough signal that we could even attempt to measure this effect.