[python #UDU-328126]: Fwd: pointer to either technical solution or code or person -

Greetings!

I'm by no means an expert in solving these problems, but for similar types of 
problems I've usually seen people use the PyPROJ library, which wraps the 
widely-used PROJ library. In this GitHub comment:

https://github.com/Unidata/MetPy/issues/893#issuecomment-861149250

You can find a link to a notebook using PyPROJ to re-project some lightning 
data from a geostationary satellite. When using PROJ/PyPROJ, the Nearside 
Perspective as a projection might also be helpful:

https://proj.org/operations/projections/nsper.html#nsper

Hope this helps,

Ryan

> Hi Ryan:
> 
> I took an AMS sponsored course a couple of months ago re python and
> atmospheric science, and found your name from looking through the
> distributed notes.  Hope it's ok to contact you.
> 
> We are working on a mechanism to protect EESS radiometers from 5G/6G
> transmissions, and to enable spectrum sharing between these entities (some
> references below). We've built parts of a prototype.  From the satellite's
> perspective have been using a python library based on TLE data (
> http://rhodesmill.org/skyfield/) which works well for nadir position of the
> satellite (<< 1/2km off), but we find that calculating the pixel center for
> crosstrack radiometers shows pretty large (10s of km) errors when the
> radiometer is at the edges of the scan.  It's particularly bad for ATMS,
> which has such a large scan angle.  We calculate the error based on
> measurement data downloaded from the radiometer (
> https://sounder.gesdisc.eosdis.nasa.gov/opendap/JPSS1_Sounder_Level1//SNDRJ1ATMSL1B.2/2021/co
> ntents.html).
> 
> I believe part of the error maybe related to using a spherical earth model
> for finding the distance from satellite to pixel center (using the
> boresight angle and the distance from sat to ground for nadir - see the
> attached picture & reference) rather than using an ellipsoidal/WGS84 model,
> but I have had trouble finding a relatively simple description of an
> ellipsoidal solution or some code that I can either use or at least look.  *I
> assume this is a problem that has been solved before!*  (note that we've
> been using a python library - https://pypi.org/project/PyGeodesy/ -  for
> most of the other spherical geometry calculations.)


Ticket Details
===================
Ticket ID: UDU-328126
Department: Support Python
Priority: Low
Status: Closed
===================
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