Impact Craters on Earth, a deep space proof on our Planet
When we look at the Moon we can easily distinguish dozens of craters caused by the collision of large meteorites or comets with its surface. The same happened on Earth’s surface mainly during its early history but very few people know that a similar event could happen again.
Nevertheless the rate of crater generation on Earth has been since 4 billions of year considerably lower, but it is still appreciable. Our planet experiences from 1 to 2 impacts large enough to produce a 20 km diameter crater about once every million years on average.
Tenoumer crater age is estimated to be 21,400 ± 9,700 years old. Despite looks like a martian crater it is located on Sahara desert.
Even though Atmosphere and Earth’s active surface phenomena quickly destroy the impact record, about 200 terrestrial impact craters have been identified and catalogued. The diameters of these craters range from a few tens of meters up to about 300 km.
With the sharp eye of Copernicus Sentinel-2 we show the most significant ones highlighting the diameter.
Most of them are located on desert areas where the erosion effects of the atmosphere are less intense and of course are more visible due to the lack of vegetation. Nevertheless we got interesting examples also on highly populated places.
3D animation created using Sentinel-2 data projected over SRTM DEM
Scientist have computed that some of these craters (diameter > 10-100km) could have caused important climate effects during the Earth’s life inducing glaciations and cooling eras with massive extinctions events (e.g.Cretaceous–Paleogene).
References: Wikipedia.
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