Thermal Asymmetry and Volatile Stratification in the Interstellar Comet 3I/ATLAS

This research note examines the unusual CO₂-dominated outgassing of the interstellar comet 3I/ATLAS. It proposes that the object’s distinct chemistry and thermal behaviour arise from formation outside the Solar System under different physical conditions. A low-conductivity crust may allow CO₂ to sublimate before H₂O, creating early CO₂ activity while deeper water ice remains stable. The note outlines five testable predictions for future spectroscopic and thermal-IR observations, providing a natural, physics-based explanation without invoking exotic mechanisms.