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Interactive tutorials and reference material for the satkit package, organized from foundational concepts to advanced applications. Tutorials are Jupyter notebooks with runnable code; theory pages provide deeper mathematical background.

Foundations

Core concepts that underpin the rest of the library.

Tutorial Description
Time Systems UTC, TAI, TT, TDB, UT1, GPS conversions and why they matter
Quaternions Constructing, composing, and interpolating 3D rotations
Coordinate Frames GCRF, ITRF, TEME, and the rotations between them
Geodetic Coordinates The itrfcoord data type: geodetic, Cartesian, and local tangent planes
Keplerian Elements Orbital elements, Cartesian conversion, and two-body vs numerical propagation

SGP4 Propagation

Analytic mean-element propagation from TLEs and OMMs.

Description
Theory: TLEs, SGP4 & OMMs TLE/OMM formats, SGP4 history, and mean-element ephemeris concepts
Two-Line Element Set Loading and using TLEs with SGP4
TLE Fitting Fitting TLEs from state vectors
SGP4 vs Numerical Propagation Comparing analytical and numerical orbit propagation

Numerical Propagation

High-fidelity force-model propagation with Runge-Kutta and Gauss-Jackson integrators.

Description
Theory: Force Model Modeled forces: gravity, third-body, drag, SRP, solid Earth tides, GR
Theory: ODE Integrators RKV / GJ8 integrators, step-size selection, tolerances
Theory: State Vectors, STM & Covariance satstate class, state transition matrix, covariance, maneuvers
Theory: Maneuver Coordinate Frames RTN / NTW / LVLH definitions and when to use each
GPS Example GPS orbit fit against ESA SP3 truth, integrator comparison
Orbit Maneuvers Impulsive maneuvers, frame choice, low-thrust orbit raising

Applications

Common tasks built on top of the core library.

Tutorial Description
Plots Plotting satellite orbits and ground tracks
Satellite Ground Contacts Computing satellite ground contacts and visibility
Eclipse Computing satellite eclipse times
Sunrise & Sunset Computing sunrise, sunset, and twilight times
Optical Observations Simulating optical satellite observations

Advanced Topics

Specialized capabilities for mission analysis and design.

Description
Theory: Lambert's Problem Algorithm details: Izzo's method, Lancaster-Blanchard parameterization, multi-revolution solutions
Lambert Targeting Orbit transfer design with delta-v computation and pork-chop plots
Planetary Ephemerides JPL DE440 and low-precision Sun/Moon/planet positions
Atmospheric Density NRLMSISE-00 density profiles, solar activity effects, and drag
Covariance Propagation State transition matrix, uncertainty growth, and orbital frame analysis
Orbital Mean-Element Message Working with OMM records