Recently geologists from Greenland was able to find the impact crater, which is the largest and the oldest on the planet. Crater with a diameter of 600 kilometers remained from hitting the 30-kilometer asteroid, who visited Earth in about three billion years ago. Apparently, on the development of life is a cosmic accident no influence not provided.

Let me remind you that until recently the largest crater formed as a result of the fall of celestial bodies, was the Vredefort, which is in South Africa, 120 kilometers from Johannesburg. The diameter of the crater is 250-300 kilometers. According to geologists, he is following the fall of the asteroid with a diameter of ten kilometers. Happened this catastrophe about two billion and four million years ago, i.e. during the Proterozoic era.

It should be noted that the crater Vederford very, very lucky, because it is in an accessible location. This is why researchers can spend on learning as much time as you want (well, to be quite honest, as long as the grant runs out). That is why for a long time the largest impact crater on Earth was thought it was he, and not the crater of the Wilkes Land, located under the ice sheet in the region of the same name of the territory of Antarctica.

Although the existence of this unique geological formations scientists guessed since the 60-ies of the last century, however, the first evidence of its existence were obtained only in 2006. Then a group of scientists led by Ralph von Frese, Laramie Potts, after analyzing the data of measurements of the gravitational field of the Earth by satellites GRACE, discovered a mass concentrate, the diameter of which was about 300 kilometers. Around him, according to the radar, there was a large ring structure - that is, the overall diameter of the crater was about 500 kilometers.

Scientists were convinced that discovered exactly impact crater because this structure is typical for them. Later, in 2009, other studies performed with the help of satellites, confirmed the data received GRACE. That is the very existence of the crater at anybody does not cause doubts. But to reach it and to conduct geochemical analysis of rock on the place of the funnel is not yet possible. Because of this, scientists are not yet able to determine the age of this education.

Furthermore, the lack of geochemical data also leads many researchers to doubt that this is the impact crater (not Caldera some exotic volcano, for example). That is why until now the leader of impact craters was considered Vederford, the second place was occupied by the canadian crater Sudbury (200 kilometers in diameter), and the third was an ominous Mexican Chikushou, the Creator of which is in vain, cause the destruction of the dinosaurs (for more details read the article "Who killed the dinosaurs?") - its diameter is about 170 kilometers.

However, judging by everything, this rating craters in the near future will have to reconsider, because Danish geologists have stated that they have found in Greenland crater even bigger than Vederford and Wilkes. The remains of this gigantic crater located near the city of Maniitsoq on the West coast of the world's largest island. Now from the original crater remained only trench width of about 100 kilometers. However, according to calculations of scientists, his real diameter equal to 600 km at the depth of craters in 25 kilometers.

According to the discoverers, they found a giant pit was formed in the result of collision with our planet thirty-kilometer asteroid. This happened about three billion years ago. It turns out that mangitakse crater is not only the largest on Earth, but also the oldest. However, why such a "elephant" scientists couldn "find" before?

The fact that time, as well as geological and climatic processes on our planet, for all these three billion years have destroyed the outer structure of Maniitsoq. In well-preserved only the deepest part of it. On them, but rather on their unusual appearance, and drew attention in 2009 employee Geological survey of Denmark and Greenland Dr. Adam Garda. He immediately suggested that this strange depression is a remnant of the impact crater.

Within three years Garda and his colleagues sought to prove his hypothesis. And such have been found - the researchers found granitoidov rocks that were crushed and melted. Such strain can only be explained by a sudden and severe blow. Interestingly, granites of this type are found only on the site in the 35 x 50 kilometers, is likely asteroid hit there.

"Something similar can be seen in the geological faults, but not with a diameter of 100 kilometers" - said the co-author of opening the doctor Ian MacDonald from Cardiff University (UK). The scientist also notes that there is other evidence. For example, quartz deposits in the impact zone have cracks and defects, which are very consistently meet similar samples of known impact craters.

When the researchers measured the angles between the cracks and orientation of each quartz crystal, the results coincided with painting, the shock wave. That is, it was not a random pattern, formed by tectonic compression and stretching that come with the volcanic eruptions and earthquakes.

Thus, according to the Danish geologists, evidence that Maniitsoq is the impact crater, is enough. However, not all agree with this. For example, a geologist John Spray from new Brunswick University (Canada) said that a: "sadly, hardly someone will be able to prove that this crater. And at the same time no one can refute it. Probably, there is on Earth and other equally ancient craters, but we do not recognize as such".

However, scientists from Denmark do not lose heart and looking for new evidence for his hypothesis. At the same time some of them and think about what could be the consequences of the fall of such a large celestial body. Dr. Garda am sure that living things are not particularly noticed this event, because three billion years ago the Earth was inhabited by only a variety of bacteria. But if the asteroid fell in our days, we, probably, would have suffered many...