Asteroid Attacks Significantly Altered Ancient Earth

This is an artistic conception of the early Earth, showing a surface pummeled by large impacts, resulting in extrusion of deep seated magma onto the surface. At the same time, distal portion of the surface could have retained liquid water.

Credit: Simone MarchiNew research shows that more than four billion years ago, the surface of Earth was heavily reprocessed – or mixed, buried and melted – as a result of giant asteroid impacts.

A new terrestrial bombardment model based on existing lunar and terrestrial data sheds light on the role asteroid bombardments played in the geological evolution of the uppermost layers of the Hadean Earth (approximately 4 to 4.5 billion years ago).

An international team of researchers published their findings in the July 31, 2014 issue of Nature.

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