Here, we have evidence that methanol ices exposed to galactic cosmic rays can replicate the colors of Arrokoth.

Organics formed indicate that Arrokoth is rich in sugars including biologically significant ribose and glucose, while aromatic hydrocarbons are essential in producing the ultrared color slopes. Our findings provide insights into the surface evolution of planetesimals in the early Solar System ranging from the Kuiper Belt to Oort’s clouds as repositories of short and long-periodic comets.

The formation of abundant sugar-related molecules dubs Arrokoth as a sugar world and provides a plausible abiotic preparation route for a key class of biorelevant molecules on the surface of KBOs prior to their delivery to prebiotic Earth.