Moon rock study reshapes timeline of ancient lunar impactsby Clarence OxfordLos Angeles CA (SPX) Sep 30, 2025When Apollo 17 astronauts returned with lunar rock sample 76535, they unknowingly carried back a fragment that would continue to puzzle scientists for decades. The rock formed nearly 50 kilometers below the Moon's surface yet shows little evidence of the violent shocks expected from such depths. That adjustment alters the timeline of lunar impacts and forces a recalibration of how scientists chart the bombardment history of Earth and other inner planets. "This rock may be small, but it carries a huge story about the Moon's early history. By showing that large impacts can raise deep material without shocking it beyond recognition, the study simplifies what had been a complicated explanation involving multiple impacts across the Moon's surface.