Astrodynamics simulations provide a crucial input to space mission planning and operations. Interactive visualisation of mission configurations, particularly for multi-spacecraft constellations or formation-flying scenarios, play an important role in both understanding options and communicating outcomes to a variety of end users or audiences. Although the mathematical foundations of idealised orbital dynamics are well understood, in practice, spacecraft orbits are much more complex. This includes factors such as the interaction between a satellite with the local space environment (e.g., aerodynamic forces) or the impact of increasingly congested orbital zones and debris fields, which may require sudden orbit changes to avoid collisions. Mission simulation must now consider both individual satellites and multi-spacecraft configurations, which may include constellations sharing an orbit or satellites flying in a multi-aperture/multi-sensor formation.

The focus of this report is an examination and assessment of astrodynamics software tools for spacecraft mission planning, simulation, and visualisation. This includes an investigation of the capabilities of a suite of open source and commercial software options. The research methodology employed a literature assessment of academic papers and technical reports that considered calculation of orbital dynamics, or demonstration of use cases linked to specific examples of commercial or open-source software. For each software option, consideration is given to factors such as:

• Technical requirements (platform, operating system, specifications)
• Availability of documentation and training materials
• Assessment of core functionality and level of extensibility
• Suitability for target applications in multi-spacecraft mission planning and operations
• Nature of visualisation modes supported for decision-making, project scoping, education, and communication.

Furthermore, engagement with SmartSat partners and end-user communities was carried out to establish specific needs for astrodynamics simulation and visualisation capabilities. This helped contribute to the selection of simulation software for evaluation as well as providing inputs to the development of metrics (e.g., accuracy of astrodynamics simulations, performance benchmarks, easeof use, financial factors) for an evaluation framework. The authors acknowledge the contributions of
the organisations who generously contributed their time and insights.