Visualizing Inner-Coma Dust Activity for Optical Instruments Observing Dynamically New Comets

Future comet flyby missions, including ESA’s Comet Interceptor, may observe targets for which nucleus morphology and activity state may be poorly constrained before encounter. This creates a need for modelling tools that can convert plausible activity scenarios into observation-like visualizations under realistic illumination and viewing geometry.

We present a synthetic imaging workflow for visualizing inner coma dust activity around irregular cometary nuclei, including both localized dust jets and the surrounding near-nucleus dust environment. The workflow is developed around open-source and openly accessible physical models and visualization tools, using Blender for procedural nucleus generation, scene construction, and physically based volumetric rendering. The method combines facet-scale surface temperature evaluation, morphology based active region selection, diffuse coma modelling, procedural or mission derived nucleus shapes, and observation geometry controlled rendering. Localized dust jets are generated where sublimation favourable surface conditions coincide with steep or topographically distinct terrain, producing plume-like volumetric structures embedded within the broader inner coma scene.

The framework has been benchmarked against independent thermophysical models and compared with calibrated Rosetta/OSIRIS observations of comet 67P using reconstructed spacecraft geometry. The resulting workflow supports rapid generation of synthetic flyby scenes for dynamically new or previously unvisited comets, providing a practical tool for interpreting activity signatures and preparing future mission observations.

Because the framework is implemented in Blender, the full 3D scene and virtual observing geometry can be reconfigured to test different flyby trajectories, illumination conditions, fields of view, and camera setups for different instruments within the same synthetic environment. The modular structure of the workflow further allows the underlying physical and rendering components to be replaced by instrument specific or higher fidelity alternatives while preserving the same scene generation pipeline.