Scientists are suggesting that two different meteors, not a single strike, may have wiped out dinosaurs some 65 million years ago. Interestingly, they struck Earth thousands of years apart.
The discovery of the second impact crater (located in Ukraine) actually was reported in 2002 but scientists were unsure of how the timing related to the original impact crater (located in the Gulf). In their current study, scientists are examining fossil plants that have filled the crater and more specifically, ferns.
Ferns have an amazing ability to bounce back after catastrophe. Layers full of fern spores - dubbed "fern spikes" - are considered to be a good "markers" of past impact events.
However, there was an unexpected discovery in store for the scientists. They located a second "fern spike" in a layer one meter above the first, suggesting another later impact event. Professor Simon Kelley of the Open University, who was co-author on the study, said: "We interpret this second layer as the aftermath of the Chicxulub impact."
This shows that the Boltysh and Chicxulub impacts did not happen at exactly the same time. They struck several thousand years apart, the length of time between the two "fern spikes".
So scientists are beginning to think that Earth possibly endured a meteor shower that spanned thousands of years, which is sort of insane and frightening to think about. It's fully possible that they'll discover more evidence of impact events in the future. [BBC]