THEMIS & 4.7



Question: Does the THEMIS team release their images pre-aligned, north up?


I thought so, until I applied my proven measuring technique to this visible light image.


One might notice north is not notated like ESA, or even Google Earth notates north.


That should have been my first clue to look more closely than I apparently did.


This is one of the disadvantages to working alone. There’s no one asking me questions or challenging my ideas.


That said… J


All I can say for sure right now is that the image is oriented precisely 2.35 or (4.7 / 2) degrees off Cydonia north as established by my geometry map.


Let me show you what 2.35 degrees looks like and how I figured this out, meaning aside.


I know from my geometry work that the D&M’s axis of symmetry is precisely 10.5 degrees off Cydonia north.


Also note precisely where a Cydonia north line exits the top right corner of FOM. For further explanation of why that’s important, see this page.


(This image created from my personal geometry .psd file. )




Here is another frame of reference for Cydonia north using my geometry map. In this image, simply note where the north line penetrates the south ‘crater’ when the line is situated in the middle of the Fort’s ‘alignment circle’.

(This image created from my personal geometry .psd file.)




I thought I knew from ESA’s latest Cydonia release that the geometric framework of Cydonia is indeed offset 4.7 degrees from true Mars north.


Notice ESA released the following image with north notated, but pointing straight right. Why?


In the following images, I simply rotated ESA’s image –90 degrees to get started.


Rotate that image 4.7 and there you have it.


Or so I thought.


Now, take a look at the THEMIS image in question, # V12445004. Something pulled me towards this image last night.


Here’s what happened when I dropped in a perfect vertical line.



That looks pretty close to this, doesn’t it?

(ESA image)


Well once again, the key is in the geometry. It all begins with one precise 60 degrees angle.


Assuming Themis oriented their image north up and I’m right about Cydonia north being offset from true north by 4.7 degrees, these are the steps I should have to take in order to make this work.


Step 1. Rotate, their image 4.7 degrees.


Ok, that looks good…

(Image rotated 4.7 degrees.)



Now, all I should have to do is copy and paste two north lines, rotate one of them 10.5 degrees and the other one -49.5 degrees.


Theoretically, that’s all I should have to do to make the geometry fit.


The geometry should just ‘snap’ into place. It doesn’t.


(Image rotated 4.7 degrees)


So, guess what the magic number is to make everything ‘snap’ together…



The magic number is 2.35 degrees.


All I had to do was rotate the image back –2.35 degrees and everything fell into place as you can plainly see above.


The biggest question I have right now is about this particular image.


(Image source)



Who oriented it and why? The ‘blockies’ do follow a perfect vertical line.



This is the image that sparked this whole business of 4.7




Along with this image…



There is something very significant about all of this.


Hopefully some answers will surface in the very near future.


The answer may actually be that Cydonia’s north is offset 2.35 off north.


Here’s what the geometry looks like on ESA’s big image rotated 2.35 degrees:


It doesn’t work as ‘tightly’ as the THEMIS images do, but it seems to work good enough.


I think I may have given up too easily.



The only real problem I have with the above work is how the D&M’s left arm doesn’t appear to fall on the same side of the line as it does on the THEMIS data.


Other than that, on second thought, it works very well.


So, the moral of the story…


Keep going! J


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