The Earth hitting after 35% meteorites enter atmosphere does not break

A small impact crater discovered in the Egyptian desert could change the calculations of risk of impact on our planet, according to a recent study. The Kamil crater, one of the best preserved of those found on the Earth, was discovered in February during a survey of satellite images with Google Earth. It is believed that the crater was formed in the last two thousand years. 

The Italian and Egyptian crater found recently visited and studied the hole 45 meters wide by 16 deep. They also collected thousands of pieces of space rocks scattered in the surrounding desert. Based on the calculations, the team believes that a solid iron meteorite, almost intact, between 5,000 and 10,000 kilos crashed into the desert at speeds in excess of 3.5 kilometers per second.

 There are no hard numbers on the number of meteorites of this size now would be a collision course with Earth, but scientists believe the potential threat could be tens of thousands. The current impact models point out that iron meteorites approximately this size and mass should be broken into smaller pieces before crashing into Earth. Now, the existence of this crater implies that up to 35 percent of these iron giants whole could survive and thus have greater destructive power. 

The calculation of the risk of impacts on Earth is not an exact science, given that so far have found only 176 impact craters, as Earth Impact Database, a database maintained by the University of New Brunswick, Canada. Most models are based on the number of these impact craters on the moon, which has almost no atmosphere and therefore does not experience the same processes of erosion on Earth. 

"Current models predict that in a million years would have formed on Earth about one thousand to ten thousand such craters," said study co-author Luigi Folco, a scientist at the University of Siena, Italy. "The reason they are rare, however, is that on earth there are a lot of erosion and small craters are easily eroded or covered." Folco and his colleagues were particularly surprised by the fact that the newly discovered crater, bowl-shaped, has a prominent scheme ejection of rock built by the original impact. Known as ejects rays, are often seen on other planets and moons with atmospheres fine. 

Exact age is unknown Egyptian crater, the team reports in the online edition of the journal Science. Geological evidence speak of a relatively recent, as Folco, but is unlikely to have been human beings who might witness the impact. "During our fieldwork we could see that part of the rock material ejected from the crater covers prehistoric structures in the area," said Folco. "We know from the literature that human occupation of this region ended about 5,000 years, with the advent of hyper-arid conditions. Therefore we believe that the impact occurred later." 

if it's more likely that future Egyptian rock-meteorites remain intact, their energy in the impact would be more concentrated, causing further damage, said John Spray, crater expert at the University of Brunswick.  However, the probability that the meteorite impact in critical to society as a big city, would be reduced, because the rocks would spread not so much "Overall, the impact threat is probably greater than people think, but historically there is little information, and we do not collect data so long ago," said Spray. "Our knowledge is very limited, so that incidents like this are very important as they help us understand the frequency and nature of impacts that affect our planet." 

A few years ago was first observed (2006) a crater 500 kilometers in diameter, which is considered the largest discovered so far (the Chicxulub crater is barely 170 km) and is believed to have formed about 250 million years after the impact of an object about 50 km. The observations were made with ground radar and gravity of the GRACE satellites, NASA. 

Its impact coincides with the mass extinction that occurred at the border of the Permian and Triassic extinction occurred when 90% of life forms. Its location in the Wilkes Land meteor suggests that also had something to do with the breakup of the super continent Goodwin, creating or accelerating the tectonic rift that since Australia began to push north. 

Recently it has been determined that there was a second hit which is located in Ukraine, raising the possibility that Earth may have been bombarded by a meteor shower.