Kiladze Caldera: A Possible Cryovolcano on Pluto

Abstract In contrast with regional primarily methane composition, Kiladze and its surroundings exhibit a water-ice spectral signature that carries an ammoniated compound, similar to two other cryovolcanic sites on Pluto. The faulted structure of Kiladze, including shaping by numerous collapse pits and the distortion of the shape of the depression, are compatible with the surroundings in Hayabusa Terra, east of Sputnik Planitia. They are further compatible with an interpretation as a caldera formed during an era of an active cryovolcanic period that appears to be significantly more recent than the overall age of the planet’s surface, possibly in the last several million years. In view of the size of the caldera and the large scale of the surrounding distribution of water ice, we suggest that Kiladze may have been a cryovolcano, in which one or more explosive events may have erupted ∼1000 km 3 of icy cryomagma onto the surface.