4 Billion-Year-Old Oort-Cloud Comet 1000x Mass of the Impactor that Caused the Extinction of the Dinosaurs



But our Pale Blue Dot will be safe. “While Comet Bernardinelli-Bernstein (C/2014 UN271) is far too small to blast a Moon out of Earth, it is big enough that it would cause a global catastrophe if it hit Earth. It probably has about 1000x the mass of the impactor that caused the extinction of the dinosaurs. But Comet BB is definitely not going to hit Earth!,” astrophysicist Gary Bernstein wrote in an email to The Daily Galaxy.