Measuring titanium in Apollo rock to uncover moon's early chemistry

Earth and the moon may look very different today, but they formed under similar conditions in space. In fact, a dominant hypothesis says that the early Earth was hit by a Mars-sized object, and it was this giant impact that spun off material to form the moon. But unlike Earth, the moon lacks plate tectonics and an atmosphere capable of reshaping its surface and recycling elements such as oxygen over billions of years.