海王星 ALPO-Japan Latest

Neptune Image 2016/09/21(UT)

Stanislas Maksmowicz,Milika-Nicholas
S.Maksmowicz,Milika-Nicholas

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Here are the reports for Uranus and Neptune performed
with the 305mm Cassegrain re-installed last 21st sept.

[Stanislas Maksymowicz  Ecquevilly,France]

In total we captured 7 images of Neptune  using the iR610nm filter where bright spots were clearly revealed - 
we quickly processed the first capture, detected spots on the F limb & settled in to capture as many subsequent images as possible. :)
I include all the single images here in a composite representation, a reversing animation of all 6 iR610nm captures plus another animation where 
I combined each consecutive capture set & made this one where each frame used these combined stacks, 
eg stacks #1...#2...#3...#4...#5. This is the larger-scaled animated gif 
which has also been orientated in WinJUPOS to display North as straight up.
 
Also the 570nm image that I mention below...
On this night  the aforementioned processing "on the fly" enabled us to watch the progression of a 
Northern complex that we "think" that we might well have captured more than once already this 
2016 apparition, but I would really need to check back through our data to be more certain - 
other AA imagers have also recorded this BWC - or at least similarly-positioned ones if they are not all one & the same! ;) 
Of additional interest to us was the appearance of what we'd describe as a "twin-complex" 
BWC in a more central region of the planet's disk...speculating that this might also be "changes" 
in the larger, more amorphous bright area we (& others!) have imaged previously...
although I appreciate that there is quite a lot of "speculation" in all this..! ;) 
There are also other, fainter bright areas as well as a regular, advancing pattern of darker albedo 
(the darker, Northern hemisphere?) whose veracity appears to be confirmed in the animations as well as that of the BWC's... 
I measure the Northern spot at roughly 20.5ｰN centred around L258ｰ...
the preceding spot of the double-feature at about 37.5ｰ & L208ｰ with its' companion (closer to the F limb) 
at about 40ｰS around L253ｰ.  (B" - planetographic as I understand the WJ measurements.....
although I readily confess image measurements are NOT my forte & there is a large element of uncertainty in my efforts therein..! ;) )
Also a final capture in iR570nm where we increased the image scale very markedly...
this was also captured using a substantially lower histogram but the results were very encouraging, 
suggesting these capture settings might be worth trying again for our next session... ;)









[Milika-Nicholas:Adelaide,South Australia]

ALPO-Japan Latest Neptune Section	2016/09/22
	2016/09/14