Climate change caused by a massive asteroid collision 466 million years ago. That is what geologists suggest in a new study.
|Asteroids collision causing climate change | Science Blog.|
Ice age 466 million years ago caused by a collision between asteroids. Geologists published tha research in the journal Science Advances.
Ice age caused by colliding asteroids?Four hundred sixty-six million years ago, a 150-kilometer diameter asteroid crashed into an unknown object somewhere between Mars and Jupiter. A team of geologists from the University of Lund in Sweden discovered that this caused a rain of space dust to fall on the Earth for 2 million years.
This gradual rain of dust would have led to less sunlight reaching the Earth, causing the seas to freeze and an ice age to begin.
Asteroid materialThe team examined rocks in southern Sweden and near the Lynn River not far from St. Petersburg in Russia for the presence of material from space. With isotope analysis, they found relatively large amounts of meteorite material in rock layers of about 466 million years old, at the time of the asteroid collision.
The team then compared these results with earlier studies in which the starting point of sea level drops had been determined. The moment at which the first space dust from the collision descended, appeared to correspond precisely with the moment at which the sea level started to fall.
Because a drop in sea level is an indication of freezing seas and ice age conditions, the geologists believe that there is cause and effect. The timing seems perfect,' says research leader Birger Schmitz.
There is constant dust falling from space to Earth. Most of the dust comes from the Earth itself, for example, from volcanoes and deserts.
But the team discovered that the asteroid collision had caused so much space dust on Earth - 10,000 times more than usual - that it was enough to change the climate significantly.
Philipp Heck, a co-author of the study, emphasizes in a press release the slowness of that process: We are talking about periods of millions of years.
What happened here is entirely different from the climate change caused by the meteorite that killed the dinosaurs 65 million years ago. It is also very different from global warming that we see today.
Partly because the climate cooled down so gradually, life on Earth was given time to adapt. This climate change eventually resulted in an explosion in biodiversity, also known as the Great Ordovician Biodiversification Event (GOBE), named after the era in which this explosion took place.