The Moon is remelted by Earth's pull
Locked in a gravitational tug of war, the Moon is kneaded until parts of it melt again.
- When
- Known to
- ± 30 million years
- Era
- Hadean
A striking number of lunar rocks give ages near 4.35 billion years, long taken as the Moon's formation date. Recent work argues instead that orbital resonance with Earth drove intense tidal heating at this time, remelting much of the Moon and resetting its rocks' clocks. If so the Moon is older than its rocks appear, and the apparent conflict between lunar sample ages and zircon ages dissolves.