satkit 0.2.5

Satellite Orbital Dynamics Toolkit

Satellite Toolkit with Rust

An accurate, high-performance satellite orbital kinematics toolkit, written in Rust with a sensible interface.

Github

Crates.io

PyPi

Language Bindings

• Native Rust bindings
• Python bindings for compiled rust code ... speed of Rust with convenience of Python
  Install with pip install satkit
  PyPi includes binaries for windows, macos (Intel & arm), and linux

Features

• Timescale transformations (UTC, GPS, UT1, TBD, TT, ...)
• High-precision coordinate transforms between:
  • International Terrestrial Reference Frame (ITRF)
  • Geocentric Celestial Reference Frame (GCRF) using IAU-2000 reduction
  • True-Equinox Mean Equator (TEME) frame used in SGP4 propagation of TLEs
  • Celestial Intermediate Reference Frame (CIRF)
  • Terrestrial Intermediate Reference Frame (TIRF)
  • Terrestrial Geodetic frame (latitude, longitude)
• Geodesic distances
• SGP4, and Keplerian orbit propagation
• JPL high-precision planetary ephemerides
• High-order gravity models
• High-precision, high-speed numerical satellite orbit propagation with high-order efficient Runga-Kutta solvers, ability to solve for state transition matrix, and inclusion following forces:
  • High-order Earth gravity with multiple models
  • Solar gravity
  • Lunar gravity
  • Drag (NRL MISE-00 density model)
  • Radiation pressure

ODE Solvers

The high-precision numerical satellite orbit propagation makes use of standard Runga-Kutta methods for integration of ordinary differential equations. The ODE solver is included as part of the library.

The methods use Runga-Kutta pairs for ODE integration and error estimation generated by Jim Verner: https://www.sfu.ca/~jverner/

References, Models, and External Software.

The equations and many of the unit tests underlying this work are drawn from the following sources:

• "Fundamentals of Astrodynamics and Applications, Fourth Edition", D. Vallado, Microcosm Press and Springer, 2013.
  https://celestrak.org/software/vallado-sw.php
• "Satellite Orbits: Models, Methods, Applications", O. Montenbruck and E. Gill, Springer, 2000.
  https://doi.org/10.1007/978-3-642-58351-3

This code makes reference to and relies on models generated by the following:

• SGP4 Orbit Propagator - https://celestrak.org/software/tskelso-sw.php
  NORAD / SGP4 orbit propagator used to generate position and velocity states from orbital ephemerides described by Two-Line Element Sets (TLEs). This code base includes a pure-rust translation of the SGP4 orbit propagator
• NRL MSISE-00 Density Model - https://ccmc.gsfc.nasa.gov/models/NRLMSIS~00/
  NRL model of air density, including density at high altitudes, used in to compute satellite drag
• Gravity Models - http://icgem.gfz-potsdam.de/home
  International Center for Global Earth Models (ICEGM), collection and archive in a common format of all existing global gravity field models
• Space Weather - https://celestrak.org/SpaceData/
  Space weather used to modulate the air density used in drag calculations
• Earth Orientation Parameters - https://celestrak.org/SpaceData/
  Time-varying Earth orientation parameters used for time epoch conversions and high-precision rotations between the inertial and Earth-fixed coordinate frames
• IERS Conventions - https://www.iers.org/IERS/EN/Publications/TechnicalNotes/tn36.html
  International Earth Rotation and Reference Systems Service Technical Note 36 for rotation between inertial and Earth-fixed coordinate systems.

Verification

The code includes rust test modules and python test modules for verification of nearly calculations, including but not limited to:

• JPL Ephemeris - Via JPL-provided test vectors for Chebychev polynomial calculation
• SGP4 - Via SGP4 test vectors provided with original C⁺⁺ distribution

Author

Steven Michael ([e-mail])

Please reach out of you find errors in code or calculations, are interested in contributing to this repository, or have suggestions for improvements to the API.