The "scoop" on the "right" and "wrong" versions of SGP4 to use in 2025

[davidmikolas]

This excellent and authoritative Stack Exchange answer https://space.stackexchange.com/a/69583/12102 highlights the variety of different versions of SGP-based propagators, and various changes that have been made, especially in recent years. It turns out that there is a "right" SGP4 to use and several others in widespread use that are now "wrong". See also https://space.stackexchange.com/a/69577/12102