A steeply-inclined trajectory for the Chicxulub impact

A steeply-inclined trajectory for the Chicxulub impact

Figure 1. The development of the Chicxulub crater. Frames from the simulation of a 17-km diameter asteroid striking Earth at a speed of 12 km/s.

Simulations performed on the DiRAC High Performance Computing Facility have revealed the asteroid that doomed the dinosaurs struck Earth at the ‘deadliest possible’ angle.

The simulations reveal that the asteroid hit Earth at an angle of about 60 degrees, leaving a signature of its trajectory in the rocks beneath the Chicxulub Crater in Mexico.

Such a strike would have maximised the amount of climate-changing gases thrust into the upper atmosphere, including billions of tonnes of sulphur that blocked the sun and triggered the KPg mass extinction. It is thought that up to 75% of plant and animal species on Earth became extinct, including dinosaurs.

The new simulations are the first ever fully 3D numerical calculations to reproduce the whole impact event, from the moment of impact to the moment the final Chicxulub crater was formed. Results of the simulations were compared with geophysical data from the site of the impact crater to diagnose the direction and angle of impact.

The results from these simulations were published in Nature Communications (Collins et al., 2020), and attracted widespread international media attention [2, 3]. The article was also featured on the STFC website [4].