William Robinson writes with news that the Moon Mineralogy Mapper (M3), an instrument developed by NASA and sent aboard India's Chandrayaan-1, has confirmed the presence of iron-bearing minerals on the moon. This marks the beginning of an extensive examination of the composition of the lunar surface. "Isro officials said M3 would help in characterising and mapping lunar minerals to ultimately understand the moon's early geological evolution. 'The compositional map that will come out of M3 will have fantastic data on geological formation of the moon,' the official said. Researchers said the relative abundance of magnesium and iron in lunar rocks could help confirm whether the moon was covered by a molten, magma ocean early on in its history. Iron and magnesium will also indicate melting of the moon, if it happened and how it formed later. This metallic element has been found in lunar meteorites, but scientists know little about its distribution in the lunar crust."