What is Scarabaeus?#

Scarabaeus (SCB) is an open-source Python framework for spacecraft navigation and orbit determination (OD). It provides a unified, mission-agnostic environment for researchers, mission designers, and spacecraft operators who need a modular, extensible tool for interplanetary and Earth-orbital navigation.

The Problem#

Spacecraft navigation requires integrating trajectory propagation, force modelling, measurement processing, and state estimation into a single coherent workflow. Existing tools (GEODYN, ODTK, GMAT, MONTE) are either proprietary, tightly coupled to specific agencies, or lack the modularity needed for research-grade experimentation. Scarabaeus fills this gap: a fully open-source, Python-first framework with a compiled Rust back-end for performance-critical components.

What SCB Does#

Scarabaeus supports:

Trajectory propagation — Keplerian, multi-body, SRP, spherical harmonics, finite/impulsive burns, and stochastic accelerations (Gauss–Markov), using a high-accuracy IAS15 Rust integrator.
Measurement modelling — Radiometric (range, range-rate, Doppler) and optical (centroiding, angular) observables, with real DSN ramp-table and media correction support.
Orbit determination — Sequential filters (SRIF, LKF) and smoothers (LSB), batch OD, parameter estimation, covariance analysis, and measurement editing.
SPICE integration — Unified time, reference-frame, and ephemeris management via SpiceyPy.
Units safety — All physical quantities carry attached units, enforced at every calculation.

Who Should Use SCB?#

Scarabaeus is designed for:

Researchers developing or evaluating new navigation algorithms.
Mission designers performing trade studies and trajectory/OD analysis.
Students learning spacecraft navigation through hands-on, real-mission examples (e.g., OSIRIS-REx).
Engineers who need a scriptable, testable alternative to commercial OD tools.

Python 3.11+ and familiarity with NumPy/SciPy are the only prerequisites. No prior OD experience is assumed for the tutorial series.