The Impact That Made the Moon: When a Planet Hit Earth

About 4.5 billion years ago, a planet the size of Mars slammed into the young Earth. The debris from that collision became the Moon. In this documentary, we rebuild the giant impact hypothesis step by step: what Earth looked like before the Moon existed, where the impactor Theia may have come from, what happened in the hours after the collision, and how scientists test the story using Moon rocks, isotopes, and computer simulations. We also look at the biggest unsolved puzzle in the story, why Earth and Moon rocks are almost identical, and at three ideas that try to solve it: multiple impacts, the synestia model, and the 2023 proposal that pieces of Theia may still sit deep inside Earth's mantle. Some parts of this story are still scientific hypotheses, and details such as timing, distances, and the origin of Theia are debated. Scenes in the video are illustrations based on models, not observations. Subscribe to Deep Time Atlas for a new journey through Earth's deep history every week. #moon #earthhistory #documentary