Closed lcx366 closed 2 years ago
I would expect the three methods to calculate the same results — where in the documentation did you find the suggestion that one of them would return geocentric coordinates? If you'll let me know, then I'll get it fixed.
I see, all these three methods actually calculate the geocentric latitude, and is it possible to add other methods to calculate the geodesic latitude?
All three methods compute “geodetic” coordinates. I'll try to update the documentation so that all of those routines mention the word "geodetic" explicitly.
There — I have improved the documentation in 61aa8e8c2d642a39ccadc02caa233c5c2b04fa79 to hopefully make it less confusing. The new documentation will appear on the website with the next release of Skyfield!
I originally wanted to calculate the satellite's sub-point coordinates, but the following code shows that there is no difference in the results calculated by the method
latlon_of
,subpoint_of
, andgeographic_position_of
.The results are
It stands to reason that these three methods should have different results. For example, method
latlon_of
calculates the geocentric latitude and longitude,subpoint_of
calculates the geodesic latitude and longitude, andgeographic_position_of
adds the elevation on the basis ofsubpoint_of
.