Skip to content


Nyx logo

Blazing fast high-fidelity astrodynamics for Monte Carlo analyzes of constellations, interplanetary missions, and deep space orbit determination

Try it on Gitpod Featured scenarios

Versatile capabilities

  • Monte carlo analyzes
    • Propagate 100 spacecraft in high-fidelity in 4.98 seconds on a standard laptop
    • Analyze trajectories in parallel by generating their ephemerides
  • High-fidelity models
    • Multi-body gravity, solar radiation pressure, and atmospheric drag models
    • Spherical harmonic gravity fields: JGM3 and EGM2008 for Earth, JGGRX for the Moon
  • Maneuver planning
    • Differential corrector and multiple shooting for finite burn and low-thrust trajectory optimization
    • 3-DOF control laws: Ruggiero, Lyapunov, or any custom law
    • Two-body approximations: Lambert solver, Hohmann transfer
  • Spaceflight Navigation
    • Conventional and Extended Kalman filters
    • Smoothing and iteration of navigation estimates
    • Ranging between spacecraft, or between a spacecraft and a ground station
  • State-of-the-art partials computation
    • Dual Number theory for STM computation (Rabotin 2019)
    • Partials available for multibody dynamics, spherical harmonics
  • Navigation workflows
    • Leverage computational speed for simulating a OD of off-nominal trajectories
    • Cloud-ready library and application enables automation of your workflow
  • Event-based ConOps
    • Design concepts of operations by finding specific events in a spacecraft trajectories
    • Seek spacecraft and cosmic events in any celestial frame
  • State-of-the-art models
    • Planetary and solar eclipse, penumbra and visibility computations
    • NAIF DE438s planetary ephemeris by NASA
    • IAU 2018 body fixed frames (Archinal et al. 2018)
  • Orbital state transformation
    • Conversion between Cartesian states and Keplerian orbital elements
    • Central body and rotation transformations

Trusted by innovative space companies

Contact me to add your company to the list!


If some documentation needs clarification, or if you've found a bug, please open a new issue here (you'll need a free account). Otherwise, you may also create a new issue by emailing the Gitlab project directly by clicking here.

For general chatter about astrodynamics, you can join the #astrodyn room on, a secure and decentralized internet chat platform.

To contact the author of Nyx, Chris Rabotin, email


Ce que l'on conçoit bien s'énonce clairement, et les mots pour le dire arrivent aisément.

Whatever is well conceived is clearly said, and the words to say it flow with ease.

-- Nicolas Boileau Despréaux

Last update: 2021-08-03