After studying the chemical makeup of lunar rocks, scientists say they have found new evidence that disproves one of the leading theories of how the Moon formed. The evidence hinges on the presence of ...

The giant-impact hypothesis is presented as the leading explanation for the Moon's formation. The Moon's lower iron content, relative to Earth, is cited as evidence supporting the giant-impact theory, ...

Among the inner solar system, Earth is the only planet that experiences plate tectonics. A new study, using convection models, shows that Earth’s collision with the protoplanet Theia some 4.5 billion ...

The moon did indeed coalesce out of tiny bits of pulverized planet blasted into space by a catastrophic collision 4.5 billion years ago, two new studies suggest. The new research potentially plugs a ...

Earth's moon formed inside a cloud of molten rock, and may have done so before our planet itself formed, a new theory suggests. Scientists call such a cloud a synestia, a doughnut-shaped ring of ...