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Full Solution from Starting Point

(1) - Draw a local area map

Mercator type with limits [N33° - N40°] / [°W076° - W086°] .

Here I am using cos (Mean Latitude) = 0.8

Check the "230729 Fix Visual Satellite Pass Area Chart and solution" Attachment

(2) - Draw the VEGA LOP on the local area Map

To accurately draw it, plot successive ends of GC segments starting from VEGA's sub-stellar position - at N38°48.4' / W 056°53.4' on Jul 30th, 2023 01:55:00 GMT - with successive departure tracks and lengths equal to 990 NM. 

In order to start with adequate departure tracks, use a known position in the area with a known Azimuth to Vega and compute the reciprocal GC departure track from substellar point.

Since the GC segments do not cross the equator :

Reciprocal GC departure track = Body Azimuth + 180° +/- Meridians convergence correction (MCC)

[Approximate] MCC is equal to : (Longitude difference)° * (sin Mean Latitude)

e.g. from previous position N35°30' / W077°13', with Azimuth 072.4°, Longitude Difference = 20.327°, Mean Latitude = 37.153° , get MCC = 12.276° , hence CG departure track from substellar point is equal to 072.4° + 180° + 12.276° = 264.7°, which after 990 NM puts us back to N35°28.9' / W077°12.7' . Not bad for an "Approximate correction"...

The "230729 Fix Visual Satellite Pass Area Chart and solution" Attachment is using departure tracks ranging from 256° to 280° to cover Latitudes from N33° to N40°

(3) - Draw the "ISS LOP" on the local area Map

First time I am ever playing with this kind of "Satellite navigation".

I have been using heavens-above.com .

The ISS track on Earth is close to 131° over Virginia.

If the picture time were exactly known, the "ISS Lop" would boil down to only one point which is our FIX.

But since there is come uncertainty in the Picture time, I am considering - and choosing, because there could be different definitions actually - that such "ISS Lop" includes all points on Earth having an apparent ISS path with minimum angular distance to Vega equal to 4.8° (best guess from the picture).

3.1 - Through trial and error, I identified position N37.3265° / W079.2032° as fulling this criteria.

Check the "230729 Fix Visual Satellite Pass Trial 1 " Attachment.

This point is about 60 NM from the VEGA Lop.

3.2 - As a starting point then, draw a segment departing previous position at track 130°.

It crosses position N36.000°/W077.225° . From this point get a second Sky chart : quite decent as regards minimum distance Vega fly-by.

(4) - Determine the solution

The segment from 3.1 here-above intersects the VEGA Lop at a position close from N36°06' / W077°26' which I am hereby submitting as a solution to this "Position fic by visual satellite pass" problem.

Hence the picture was taken by 21:54:20 LT +/- 5 seconds of time.

Check the "230729 Fix Visual Satellite Pass Trial 2 " Attachment.

This position falls in the vicinity of Scotland Neck in beautiful NC.

For you Frank, how did you determine your own solution and how far does this one fall from yours ?

Thanks again,

Antoine M. "Kermit" Couëtte