The surface of Arrokoth, an oddly flat object on the edge of the solar system, may have been boiled away by heat from the sun.
This body, more than 6 billion kilometres from the sun in the Kuiper belt beyond Neptune, was visited by NASA’s New Horizons spacecraft in 2019. The probe flew past during an extended mission after visiting Pluto in 2015, taking images that revealed Arrokoth as a strange world with two flattened lobes.
