هل سقوط كويكبين أدى إلى انقراض الديناصورات؟
August 18, 2022 - حفرة صخمة تحت البحر تم اكتشافها حديثاً قبالة سواحل غرب أفريقيا تدفع علماء إلى التساؤل عما إذا كان انقراض الديناصورات سببه سقوط أكثر من كويكب واحد منذ 66 مليون سنة.
What appears to be a second large asteroid impact crater has been discovered under the sea off the coast of West Africa, leading scientists to speculate that it may have been the smaller cousin of the one that struck the gulf of Mexico millions of years ago, wiping out the dinosaurs.
At 9km wide, the newly discovered crater – dubbed the Nadir Crater – is not as larger as the vast Chicxulub Crater in Mexico, which is estimated to be around 180km wide and 20km deep.
However, its size, age and placement on the other side of the Atlantic Ocean is leading geoscientists to wonder if the Earth was hit by more than one space rock that fateful day 66 million years ago, or if the Nadir asteroid was a chunk that broke off the Chicxulub asteroid.
- Impact crater may be dinosaur killer's baby cousin (BBC)
- African crater adds an asteroid strike to the late dinosaur era (New York Times)
- Scientists discover a 5-mile wide undersea crater created as the dinosaurs disappeared (CNN)
- A second asteroid may have struck Earth when the dinosaurs died out (New Scientist)
- The Nadir Crater offshore West Africa: A candidate Cretaceous-Paleogene impact structure (Science Advances)