Dr Nicholson’s team has to be cautious about tying the two impacts together. Nadir has been given a very similar date to Chicxulub based on an analysis of fossils of known age that were drilled from a nearby borehole. But to make a definitive statement, rocks in the crater itself would need to be pulled up and examined. This would also confirm Nadir is indeed an asteroid impact structure and not some other, unrelated feature caused by, for example, ancient volcanism. […] Prof Sean Gulick, who co-led the recent project to drill into the Chicxulub Crater, said Nadir might have fallen to Earth on the same day. Or it might have struck the planet a million or two years either side of the Mexican cataclysm. Scientists will only know for sure when rocks from the west African crater are inspected in the lab. “A much smaller cousin, or sister, doesn’t necessarily add to what we know about the dinosaurs’ extinction, but it does add to our understanding of the astronomical event that was Chicxulub,” the University of Texas at Austin researcher told BBC News.
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