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Hi Renormaised,
Georg is an authority on planetary lightning, infact his PHD was based on it. He has very graciously sent me three of his papers on it. Specifically on Saturn's SED's "Saturn Electrostatic Discharge".
Two of these papers were published last year in Icarus and the third has not yet been published and he has asked me not to circulate it.
The atmosphere of Saturn has three well defined cloud layers. An upper layer of ammonia ice crystals, a middle layer of ammonia hydrosulphide crystals and a lower layer of water ice crystals. These layers extend to a depth of about 300 km.
The SED's are thought to originate deep within the atmosphere at about 200 to 300 km depth. They are thought to be directly due to rapid vertical movement of water clouds at up to 150 m/s, this column breaks through the upper ammonia crystal clouds and then mushrooms over the top resulting in the bright white spots imaged by amateurs from Earth.
Some times these spots have been so close together that the only way I have been able to image them is monochrome, there has simply not been enough time to RGB them they would have merged into one. Each night I do this I start with a couple of monochrome images to see how many storms are visible and if they are separated enough for me to RGB them.
I really enjoy doing this and although I am rapidly running out of time before I lose Saturn over my local horizon. When that happens I will look forward to reaquisition in the morning sky.
Regards
Trevor
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