Lunar impacts created seas of molten rock on Moon

As the lunar magma ocean cooled over millions of years, it differentiated to form the Moon\'s crust and mantle. However, according to a new analysis by planetary scientists from Brown University, this wasn\'t the last time the Moon\'s surface was melted on a massive scale.

The research using NASA\'s Lunar Orbiter Laser Altimeter (LOLA), led by researcher William Vaughan, shows that the impact event that formed the Orientale basin on the Moon\'s western edge and far side produced a sea of melted rock 220 miles across and at least six miles deep. Similar seas of impact melt were probably present at various times in at least 30 other large impact basins on the Moon.

Vaughan and his colleagues show that as these melt seas cooled, they differentiated in a way that was similar to the lunar magma ocean. As a result, rocks formed in melt seas could be mistaken for "pristine" rocks formed very early in the Moon\'s history, the researchers say.

"This work adds the concept of impact melt magma seas to the lexicon of lunar rock-forming processes," said planetary] geologist James W Head III, senior researcher of the study."It emphasises that one must consider the detailed point of origin of the rocks in order to interpret them correctly," James said in a statement.

That includes rocks brought

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