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Limb of the Full Moon Using WinJUPOS Projections

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#1 james7ca

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Posted 25 October 2021 - 06:17 AM

I posted an image of the October 20, 2021 Hunter's Moon a few days ago ( __HERE__ ) and I decided to use that image as the source for some distortion-correcting projections of the west and east limbs of the full moon. These are Lambert cylindrical equal-area mappings using WinJUPOS that reduce the foreshortening normally seen when an object appears near to the limb of the moon (well at least within about +/-30 degrees latitude and when not at the extreme edge of the moon).

 

So, below is a sized-reduced mapping of the entire face of the Hunter's full moon based upon the image I captured on October 20.

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  • Full WinJUPOS Projection (smal).jpg


#2 james7ca

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Posted 25 October 2021 - 06:18 AM

Here is a higher resolution image of just the western limb.

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  • WinJUPOS Projection West Plus Minus 30 Degrees Lat.jpg

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#3 james7ca

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Posted 25 October 2021 - 06:19 AM

And the eastern limb.

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  • WinJUPOS Projection East Plus Minus 30 Degrees Lat.jpg

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#4 james7ca

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Posted 25 October 2021 - 06:28 AM

And a comparison of the original capture (west limb) and the WinJUPOS mapping/projection (highly compressed to get under the 500KB limit on CN). I've added labels showing a few of the maria and craters that are normally seen highly foreshortened.

 

Note how Mare Crisium goes from rather round looking to its true oval/egg shape (in the WinJUOS mapping) and how Mare Smythii goes from a highly foreshortened, thin ellipse to a nearly circular feature (formed by an asteroid impact).

Attached Thumbnails

  • Western Limb.jpg
  • Western Limb WinJUPOS Projection.jpg

Edited by james7ca, 25 October 2021 - 10:13 AM.

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