Saturn Oct 11th 2021

[Quark]

Hi All,

Imaged Saturn October 11th 2021 targeting a CM transit of the 2010 GWS AV, seeing was variable with the best of it being good. Have well resolved the AV in the 685nm IR data also resolved in the R data and although quite faint it is also seen in RGB.
I measure the AV to be at approx Lat+41.7 L3 298.7. The 2021 HST OPAL data, as was also the case in 2020, resolved a series of ripples impinging up into the Southern edge of the NNTeB,one such ripple is resolved in these data at approx Lat+47.2 L3 269.7.
The North polar vortex and vertices of the polar hexagon are well resolved in the polar maps, particularly so in RGB data. Have a significant volume of data from this session, all has been uploaded to PVOL.

http://pvol2.ehu.eus/pvolimages/saturn/s2021-10-11_09-58_685nmIR_tba.gif

http://pvol2.ehu.eus/pvolimages/saturn/s2021-10-11_09-58_polar_tba.gif

http://pvol2.ehu.eus/pvolimages/saturn/s2021-10-11_10-06_r_tba.gif

http://pvol2.ehu.eus/pvolimages/saturn/s2021-10-11_09-58_rgb_tba.gif

http://pvol2.ehu.eus/pvolimages/saturn/s2021-10-11_09-57_polar_tba.gif

Cheers
Trevor

[multiweb]

Top shelf Trevor. :thumbsup::thumbsup::thumbsup:
Lucky you got clear skies. Lot of rain on the coast. I can only look at the seeing map and wish for a sucker hole. :lol:

[Dave882]

Great shots! I really like the polar projections you do and would love to know a bit more about how to put these together

[PKay]

Nice work Trevor, quite fascinating.

You certainly know that planet well!

[Quark]

Thanks Marc, rain is not often a problem out here, that said have had showers the last couple of days.

Thanks Dave. WinJUPOS is a powerful tool. There are several different ways to do polar maps. With Saturn I use the polar maps to allow me to get accurate measurements for the vertices of the polar hex. I have a very long term project to accurately measure the rotation rate of the Hex relative to L3. Also the polar maps actually reveal quite well the low contrast structure within the EZ also the AV which I have tracked since it formed in Jan 2010 is easier to identify.
So....open the Sat file in WinJUPOS.
Accurately align the outline frame, I use "With grid" (30 degrees).
Save the IMS file.
Check "Analysis" > Map computation.
I set "Map width" to 616 pixels.
Check "Sterographic polar projection"
Check "Planetographic"
Check "North up"
Compile map, then I look at the map, I want the ring shadow to be horizontal across the bottom of the map so keep adjusting the L3 at the left margin until I am happy with the orientation of the map.
Good luck with it.

Thanks Peter, Saturn is my specialty I have currently 6844 data sets on the PVOL data base, the spit would be 2/3 Saturn 1/3 Jupiter.

[Dave882]

Thanks for that detailed explanation Trevor! Hopefully we get some good conditions in the next couple of weeks so I can try it out. Much appreciated!!

[multiweb]

Got my eyes on this Sunday night. Fingers and toes crossed. :prey:

[cometcatcher]

Incredible dedication you have to Saturn Trevor! You must be eagerly waiting for large outbreak!