Asteroid that led to dinosaur extinction hit Earth at ‘deadliest possible angle’

It was a one-in-a-66-million-years shot.

The 6.2-mile-wide asteroid that crashed into the Yucatán Peninsula at the end of the Cretaceous period did so at the “deadliest possible angle,” according to a new study published in Nature Communications on Tuesday.

Had it come from any other direction, the dinosaurs might still be around today.

The doomed asteroid, which landed at a site in Mexico now known as the Chicxulub crater, is considered by many scientists to be the agent behind the demise of the dinosaurs, and 75% of all life on Earth at the time.

The new report, compiled by engineers and geologists from Imperial College London, the University of Freiburg and the University of Texas at Austin, is the first to reveal the final stages of the Chicxulub crater’s formation. Researchers used 3-D simulations of the 124-mile-wide hole’s exact shape and structure to determine that the asteroid came from the northeast, at a lethal angle of about 60 degrees to the ground.

“For the dinosaurs, the worst-case scenario is exactly what happened,” said lead researcher Gareth Collins in a news release. “The asteroid strike unleashed an incredible amount of climate-changing gases into the atmosphere, triggering a chain of events that led to the extinction of the dinosaurs. This was likely worsened by the fact that it struck at one of the deadliest possible angles.”

They explain that the impact itself wasn’t most devastating for the planet. Rather, scientists say it was a snowball of devastating climate effects that followed the event, which released billions of tons of vaporized rock, sulfur, carbon dioxide and water vapor into the air, and enveloped the globe. The result was a breathless atmosphere and an obscured sun that lasted for an estimated 18 months, during which time photosynthesizing plants and animals were choked out, and the planet descended into a rapid winter.

“We know that this was among the worst-case scenarios for the lethality on impact, because it put more hazardous debris into the upper atmosphere and scattered it everywhere — the very thing that led to a nuclear winter,” said Collins.