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Quark
20-09-2017, 01:22 PM
Have fair data from Sept 15th a couple of hours prior to Cassini loss of signal.
As the time approached for loss of signal the seeing deteriorated significantly but I felt I had to do something, produce something in honour of Cassini.

I decided to go with a 6 minute .ser capture with my 685nm IR-Pass filter, 3 minutes either side of the predicted loss of signal at 11:55:15 UTC.

My data run commenced at 11:52:06 UTC and ended at 11:58:06 UTC.
I cut this file into 6 x 1 minute .ser files and processed each one the best I could, salvaging the better frames to come up with 6 low res images. Have made an animation, albeit rather low res, from this data and attached a link to it on the PVOL data base.

I did not see a flash, the seeing prohibited such an experience but still I have produced this animation. At the start of the animation Cassini was still transmitting data but by the end Cassini would have been no more RIP Cassini.

Just for the sake of absolute historical accuracy I have attached one last image.
Given that the confirmed loss of signal and therefore “End Of Mission” was at 11:55:46 UTC I have created one final image. From my continuous six minutes of data I have cut the data from 11:53:46 UTC through to 11:57:46 and processed it to produce an image with the midpoint of precisely 11:55:46 UT.

Saturn has always been the main focus of my work, looking for SED’s related spots for Cassini RPWS has been a passion for me. Tracking the long lived anti cyclone fossil of The Great Storm for Cassini ISS has been such a challenge. Finding and tracking various other atmospheric features for other researchers has been very satisfying but I feel a loss now that Cassini is no longer out there quite sad really.

http://pvol2.ehu.eus/pvolimages/saturn/s2017-09-15_11-55-06_685nmIR_tba.gif

Regards
Trevor

AstralTraveller
20-09-2017, 02:36 PM
Thanks for the farewell images. Cassini was quite a show and taught us so much.

I hope you saw the special on Catalyst last night. I enjoyed it immensely. There are some people out there experiencing a real sense of loss now that 20-30 years of work is behind them.

geolindon
21-09-2017, 09:10 AM
Thanks Trevor and commiserations. I share your sense of loss but your's is so much greater with your intense involvement.

In your PVOL animation there is a chunky streak/spoke at about 9 o'clock on the B ring. The position and scale is wrong for Cassini but wondering what it is?

Quark
21-09-2017, 10:51 AM
Thanks David and yes I did record the Catalyst special, it was extremely well done and featured several of my contacts within the Cassini program.

Thanks Lindon, this data was abysmal and I went to great lengths to try and salvage enough frames to make the images for the animation. Due to the relatively small number of frames in the stacks their were always going to be some artifacts. I had approx 24,000 frames over the six minutes and these six images represent only about 6,000 frames with the rest thrown away. The point of making the attempt was to have at least some historical record of the moment the Cassini mission ended, even if it ended up being with less than great data. As a matter of interest I do have one frame with a sharp bright streak on it but it is just the collision of a cosmic ray with a pixel on my cameras array.