The age of the dinosaurs lasted more than 100 million years, which is an unfathomable time when compared with humans on this planet for only 300,000 years. Most dinosaur species went extinct about 65 million years ago when a large object fell into the Yucatan Peninsula. A team of scientists from the Southwest Research Institute (SwRI) is trying to determine the source of this effect, and current data suggest that similar asteroids may be more common than we thought.
Even after millions of years of weathering and structural drift, signs of this fatal impact are still visible. This 6-mile-long space rock left a 90-mile-long crater (called the Chicxulub Crater) when it hit the earth, which can still be seen with proper equipment. Many geological anomalies caused by impacts have also appeared in this area of Mexico. Analysis of rock samples from the Chicxulub crater revealed that the impactor resembled a carbonaceous chondrite. These are very old materials, and there are few chondrites of similar size today. This begs the question: Where did the dinosaur killer come from?
In the past, the team studying this event simulated the rupture of comets and larger asteroids in the solar system. The idea is that these clumps of matter may fall under the gravity of the earth, and the Chicxulub crater is the largest fragment. However, these explanations are not completely consistent with our understanding of asteroids and comets. The SwRI team decided to use computer models to track how objects escape the large and small asteroid belts between Mars and Jupiter. They are looking for “escape hatches” where the planet’s gravity can push asteroids into orbits across the Earth.
The team used NASA’s Pleiades supercomputer to simulate more than 130,000 asteroids over millions of years. Simulations have shown that carbonaceous chondrites in the outer half of the asteroid belt are particularly susceptible to being thrown to Earth. The release frequency of asteroids similar in size to the Chicxulub impactor in this area maybe 10 times as high as previously estimated.
So this is very worrying, but from a macro perspective, 65 million years is not a long time ago. The impact of SwRI analysis products like this happens every 250 million years or so. So, if we are lucky, we still have some time.