Delayed Methane Detection in 3I/ATLAS: GCR-Driven Subsurface Stratification and Interstellar Exposure Age Constraints

Akshat Rawat, Kinsuk Acharyya

Interstellar comet 3I/ATLAS shows unusual volatile activity, including strong H${}_2$O, CO, and CO${}_2$ production and a delayed post-perihelion detection of CH${}_4$. In this work, we…