The Moon formed from a giant impact of the proto-Earth with the ancient protoplanet Theia. In a new study, a team of scientists from the United States, Germany, France and China measured iron isotopes in lunar samples, terrestrial rocks, and meteorites representing the isotopic reservoirs from which Theia and proto-Earth might have formed. They found that all of Theia and most of Earth’s other constituent materials originated from the inner Solar...
