SED's Storm on Saturn 15/04/2009

[Quark]

Hi All,

Last night I imaged Saturn every 10 minutes from 12:10 UTC to 13:50 UTC to capture an electrical storm on Saturn. The storm has been active since January and is currently at longitude 350 degrees W Sys III in the STrZ (Southern Tropical Zone).

The RPWS (Radio and Plasma Wave Science) instrument on the Cassini space craft has been detecting SED's (Saturn Electrostatic Discharge), lightning from this storm. So this is not just a cloud system but an active electrical storm.

I have "R" channel images every ten minutes for 100 minutes of the transit of this storm and present them here in an animation. I also captured two RGB images at 12:40 UTC and 12:50 UTC that are attached to this post. The storm is quite apparent but I have marked it. All of these images, the RGB's and R channel images in the animation are over processed, my aim is to supply usable scientific data and in this instance not pretty pictures, that said I am pleased with how they turned out.

http://www.iceinspace.com.au/uploads/STrZstorm15042009anim.gif

The seeing was variable from 7 to 8/10, good to very good. My son, Christopher monitored the ambient and primary mirror temperatures.

Thanks for looking
Regards
Trevor

[Dennis]

Excellent work Trevor – a really top effort. The animation shows the storm very well and I don’t envy you the time and effort required to capture the data and then process it!

Cheers

Dennis

PS – Nice stills too!

[iceman]

Well picked up Trevor. Gee it's only just above the noise level sometimes.

Well imaged.

[Quark]

Thanks Mike, the temp of the primary really is most critical. I never realized just how critical. The variations in quality from frame to frame in the animation were largely caused by periods where my primary went outside of the +- .5 C. Now that I have control of the temp it really is amazing to see the image quality vary over a relatively short time scale. Over the 100 minutes of this capture session the ambient steadily dropped and on a few occasions when I had turned off the Peltier's, the rate at which the ambient was falling meant that the temp differential became to much resulting in a rapid deterioration of the image. Turning the Peltier's back on rectified the problem in about 10 minutes.



Thanks Dennis,
Yep a lot of time was involved, I am most pleased with how the RGB images turned out and by rapidly clicking between them the rotation of the planet and storm is most apparent. The rapid rotation of the planet really confines the length of time for the capture of the R, G & B channels. The shorter captures means a less smooth final image but the object was to resolve the storm.

[Kevnool]

Top image Trev, I bet your glad the jacaranda tree has gone to keep producing images.

Cheers Kev.

[Quark]

Spot on Kev,

If the Jacaranda hadn't been severely pruned then I would be having problems with Saturn right about now.

Cheers
Trevor