SatNOGS
An open-source global satellite ground-station network, client stack, and public transmitter database.
Skyfield
A production-stable MIT-licensed Python library for precise positions of planets, stars, and Earth satellites.
Basilisk
An open-source astrodynamics and spacecraft simulation framework for research, GNC, and hardware-in-the-loop work.
TudatPy
TU Delft’s open-source Python interface for numerical astrodynamics, propagation, estimation, and space research.