December 20, 20242 min readThe moon may have melted 4.35 billion years ago—explaining a lunar age mysteryBy Payal Dhar edited by Sarah Lewin Frasier Javier Zayas Photography/Getty ImagesThe moon is Earth’s closest neighbor in space and the only extraterrestrial body humans have visited. Yet scientists are still unsure exactly when a Mars-size meteorite slammed into early Earth, causing our natural satellite to form from the debris. Lunar rock samples suggest the event happened 4.35 billion years ago, but planet formation models and fragments of zircon from the moon’s surface put…
