Rubin EDP2 Shallow Coadds Yield 59 Cometary Activity Detections Including New Object 2025 NC6

The group used the Ponder orchestrator and Sorcha survey simulator to predict positions of known small bodies, then queried the Rubin Science Platform for shallow coadds containing one or two visits. They extracted cutouts from roughly 700 comet and active-object fields and visually searched for extended morphologies produced by dust or trails. This recovered activity in 243P/NEAT, 510P/Boattini, and 2008 QZ44 while adding the first reported pre-perihelion detection for the latter and new activity in 2025 NC6.

Because LSST coadds will retain regions of unequal visit depth throughout the decade-long survey, the same shallow layers will continue to supply single-visit-depth imaging. The method therefore offers an early-alert channel for newly active objects before full-depth stacks or alert streams become available. Highlighted targets 99P/Kowal 1, 510P, and 303P/NEAT now require rapid ground-based follow-up to confirm ongoing activity and refine orbits.

The work demonstrates that extended Solar System morphologies survive co-addition even when depth is minimal, directly supporting hazard-monitoring pipelines that must flag NEOs and active bodies on short timescales. Visual inspection remains the current bottleneck; automated morphology classifiers trained on these cutouts could scale the approach to the full LSST data volume.