An international team of researchers, led by scientists from the Swedish university of Lund, discovered that the breaking of a great rock in a 150-km diameter in the far asteroid belt , between the orbits of Mars and Jupiter helped, makes 470 million years ago, to "shoot" the biodiversity on the Earth.
When the asteroid broke into pieces, after a collision with another similar body, around the solar system inner is filled with huge quantities of dust, which caused an ice age on Earth and, subsequently, higher levels of biodiversity. The study has just been published in Science Advances.
During the last few decades, scientists have begun to understand that the evolution of life on our planet depends, also, of the astronomical events that happen around us. The asteroid that killed the dinosaurs 65 million years ago is just one example of this.
Now, however, and for the first time, researchers have been able to submit a very different example: an event is astronomical far with a strong impact on the evolution of life on Earth.
ice AgeMakes 470 million years ago, when the asteroid of 150 km was destroyed, the huge cloud of dust prevented for a long time that the Sun's light to reach our planet, giving rise to a long ice age. The weather, which up to that time had been more homogenous, it changed, and was divided into several climatic zones, with arctic conditions at the poles and tropical conditions in ecuador.
The huge diversity of invertebrate species that took place during that period occurred, according to the study, as an adaptation to the new climate caused by the asteroid destroyed.
"it Would be something similar to being in the middle of the room and break up a bag of vacuum -explains Birger Schmitz, professor of geology at Lund University and director of the research, only on a much larger scale".
The team of scientists came to this conclusion after measuring the helium extraterrestrial incorporated in the sediments of the sea bottom, petrified of Kinnekulle, in the south of Sweden. On their way to Earth, that dust was enriched with helium when it was bombarded by the solar wind.
"This outcome ensures Schmitz - was totally unexpected. During the past 25 years we have relied on assumptions very different to explain what happened on Earth at that time. And it was not until we had the latest measurements of the helium when it all clicked."
what Solution to climate change?The surprising finding, say the scientists, could be very useful to the hour to reverse the change to earth's climate if all attempts to reduce carbon dioxide emissions fail definitely. According to the Intergovernmental Panel on Climate Change, in effect, we are approaching a situation that reminds us of the conditions that prevailed just before that distant collision of asteroids makes 470 million years ago.
During the last decade, we have discussed various m methods artificial to cool the Earth in the event of a climate catastrophe. And one of those methods, as already shown theoretically, that could be the place for asteroids, as if they were satellites, around the Earth in such a way that they release continuously a powder and to block a portion of sunlight.
"Our findings - concludes Schmitz - show for the first time that dust has already cooled the planet ever , and in dramatic fashion. Our studies may provide a more detailed understanding and empirical, of how that process works, and that in turn can be used to evaluate if the simulations of the current models are, or are not, realistic".
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Date Of Update: 19 September 2019, 13:01
