Systematic Assessment of Comet Behavior Using the Volatile Activity Monitoring and Prediction (VAMP) Tool

The development of all-sky surveys and the upcoming LSST’s deep, wide-field capabilities will enable the discovery of many more faint and distant comets, allowing them to be tracked from the outer solar system and revealing early activity that was previously undetectable. This opens the door for more comprehensive studies of cometary evolution and volatile-driven activity, particularly for comets beyond the reach of current surveys. With this anticipated influx of consistent, high-quality data, efficient methods of assessing activity are essential. We present the Volatile Activity Monitoring and Prediction (VAMP) model—an adaptable tool that systematically evaluates cometary activity using Bayesian statistics and a range of surface and subsurface sublimation models for volatiles. We demonstrate the model’s effectiveness in recovering key physical parameters, including nucleus size, fractional active area (FAA) for water, CO₂, and CO, and temporal activity characteristics such as fading, delayed onset, outbursts, and quenching. We validate VAMP by recovering physical parameters for short-period comets with independently measured in-situ observations, and test its performance on simulated datasets. VAMP is a versatile framework for assessing and predicting comet activity and will be invaluable for future mission planning, including Comet Interceptor and spectroscopic follow-up campaigns with observatories like JWST.