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Dave Walden you wrote: Can you get a rough Lat and Long from the data below.  Observation accuracy is much below the resolution used. Date is 1 Sep 2025.

I suspect your app must already know your lat & long either via GNSS or manual input, or how can it calculate the satellite’s sextant altitude and azimuth.  However, I believe more nimble brains than mine at half past bedtime can calculate them from the screen alone.  In the diagram attached Z is the observer’s position and X is the satellite’s position.  You’re given Z the satellite’s azimuth, p the zenith distance, and z (90+dec).  That’s two sides and a non-included angle.  You can use the spherical sine rule to get your latitude x (but there’s a chance of two solutions).  Hopefully the correct answer will be obvious.  Then with two sides and two angles, there are three ways of obtaining angle P.  Given the time (do you really know UT?  You might need a bit of help with time zones), you can find GHA Aries.  Then given RA and knowing angle P, you can work out longitude. I hope that's what you meant.  DaveP

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