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A rock from the moon’s early days — Science News, March 30, 1974
Taking its last shot at the prize, the Apollo program came through. A major goal of the scientists examining samples brought back from the lunar surface was to find a rock virtually as old as the moon itself, a relic more than 4.5 billion years old.… After five visits to the moon, the last-ditch effort, Apollo 17, finally paid off.
Update
Apollo-era lunar rocks are still revealing secrets of the moon’s youth. For instance, the moon’s magnetic field — if it existed — lasted for the satellite’s first 500 million years or so, a recent analysis suggested (SN: 8/28/21, p. 7). Another sample of moon rocks, collected in 2020 by China’s Chang’e-5 mission, is providing new tidbits from later time periods. Those rocks suggest the moon was volcanically active for longer than previously thought, with lava flowing as recently as 2 billion years ago (SN: 11/6/21, p. 6). China’s Chang’e-6 mission, slated to launch in May, might deliver the first rocks from the moon’s farside. That material could explain why the near and far sides appear to be geologically distinct.
