Measurements of potassium in lunar and terrestrial rocks have disproved the leading hypotheses for the origin of Earth’s sole natural satellite. Moon. Image credit: Gregory H. Revera / CC BY-SA 3.0. A duo of researchers reports isotopic differences between Moon and Earth rocks that provide the first experimental evidence that can discriminate between the two leading models for the Moon’s origin. In one model, a low-energy impact leaves the proto-Earth...
