Simplified Perturbations Models

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Simplified General Perturbations 4 (SGP4) is a mathematical model used to calculate the position of a satellite(s) relative to an Earth-centered co-ordinate system.

When given a two-line element (TLE) that describes the current position of a satellite, SGP4 can be used to calculate the future position of the satellite (this is called propagation).

SGP4 is a term commonly used to refer to both SGP4 (near satellite) and SDP4 (far satellite) models.

Source Code is a C++ SGP4/SDP4 library. is a Python SGP4 library.


Geoffrey Hunter

Dude making stuff.

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