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New analysis of radioisotopes of meteorites and the Earth suggest the Earth formed in only a few million years via a process called pebble accretion. This may mean the Earth\u2019s water was incorporated early and gradually rather than through late impacts. Recent determinations of the historical length of the Earth\u2019s day suggest it stalled out at 19 hours for a cool billion years, and we still have a ways to go to get to 25 hours when we can all sleep in. Find out about the Earth\u2019s history, supermassive black hole mergers, and syzygy trivia.