New research shows that more
than four billion years ago the surface of Earth was heavily reprocessed – or
melted, mixed, and buried – as a result of giant asteroid impacts. A new
terrestrial bombardment model, calibrated using existing lunar and terrestrial
data, sheds light on the role asteroid collisions played in the evolution of
the uppermost layers of the early Earth during the geologic eon called the
“Hadean” (approximately 4 to 4.5 billion years ago).
The new research reveals that asteroidal collisions not only severely altered the geology of the Hadean eon Earth, but likely also played a major role in the subsequent evolution of life on Earth as well.
Source:
http://sservi.nasa.gov/articles/new-nasa-research-shows-giant-asteroids-battered-early-earth/
Image:
Spatial distribution and sizes of craters formed on the early Earth. Each circle indicates the final estimated crater size; color coding indicates time of impact.
Credit: Simone Marchi/SwRI.
The new research reveals that asteroidal collisions not only severely altered the geology of the Hadean eon Earth, but likely also played a major role in the subsequent evolution of life on Earth as well.
Source:
http://sservi.nasa.gov/articles/new-nasa-research-shows-giant-asteroids-battered-early-earth/
Image:
Spatial distribution and sizes of craters formed on the early Earth. Each circle indicates the final estimated crater size; color coding indicates time of impact.
Credit: Simone Marchi/SwRI.
CORINA MARINESCU
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