Proposed Lunar Measurements of r-Process Radioisotopes to Distinguish the Origin of Deep-sea 244Pu

^244 Pu has recently been discovered in deep-sea deposits spanning the past 10 Myr, a period that includes two ^60 Fe pulses from nearby supernovae. ^244 Pu is among the heaviest r -process products, and we consider whether it was created in supernovae, which is disfavored by nucleosynthesis simulations, or in an earlier kilonova event that seeded the nearby interstellar medium with ^244 Pu that was subsequently swept up by the supernova debris. We discuss how these possibilities can be probed by measuring ^244 Pu and other r -process radioisotopes such as ^129 I and ^182 Hf, both in lunar regolith samples returned to Earth by missions such as Chang’e and Artemis, and in deep-sea deposits.