The impact of asteroids on our planet it wiped out millions of life forms on Earth - and that shouldn't be new to anyone. However, these large space rocks they don't just bring death and destruction. a asteroid it can also be a source of life and the cause of great biodiversity, according to a study by Lund University in Sweden, published in Science Advances.
O asteroid that extinguished the dinosaurs reached the Yucatan peninsula 67 million ago, causing a direct impact on the “inhabitants” of the Land, a shower of glass and the subsequent Erthe Glacial. However, this asteroid it does not compare in size with a very important one for the history of our planet 470 million years ago, the scientists revealed.
At that time, 485 million years ago, the Ordovician period began in the Land, characterized by not having living beings on the Earth's surface due to the lack of oxygen. However, at some point the Ordovician Biodiversification Great Event (GOBE) took place. From then on, there was a massive birth of species of animals that populated the planet.
Until now, science knew what happened, but did not understand why. However, studies at Lund University show that a asteroid 3 thousand times greater than the dinosaurs 470 million years ago it was responsible for the increase in biodiversity on Earth. This was beyond the orbit of Mars and collided with a rock of similar size, resulting in a lot of dust that fell into the Land.
The consequence of this dust for the planet was the attenuation of sunlight, which reduced radiation. This, in turn, cooled the planet significantly and started an ice age that allowed the birth of new species. In this period, the Ice expanded and the ocean levels have dropped, creating shallow and isolated seas, conducive to improving the creation of new species. In addition, cold water has more dissolved oxygen, which has also improved conditions for life.
Scientists already knew about the Ice age and GOBE, but did not understand their cause. So, they decided to study the dust particles in the seabed sediments deposited at this time. Thus, they managed to confirm that these sediments come from the dust clouds of the asteroids by the presence of the helium-3 isotope, which could only have come from space.
Street: Fawer Wayer