WIREDGOV

One of the UK’s most powerful high-performance computers has helped scientists simulate the impact of the asteroid, that hit earth just under 66 million years ago and is thought to have killed dinosaurs. 

The simulations were carried out by researchers at Imperial College London, using the DiRAC High- Performance Computing facility, funded by the Science and Technology Facilities Council (STFC), as part of UK Research and Innovation (UKRI). 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.

Figure 1: Development of the Chicxulub at 60°impact. Credit: Gareth Collins/Imperial College London

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 caused a mass extinction. It is thought that up to 75% of plant and animal species on Earth became extinct, including dinosaurs.

The simulations of the asteroid impact were created by drawing geophysical data from the site of the impact and a combination of 3D numerical impact simulations, performed by STFCs DiRAC. The new models are the first ever fully 3D simulations to reproduce the whole event, from the moment of impact to the moment the final Chicxulub crater, was formed.

DiRAC Director, Professor Mark Wilkinson from the University of Leicester, said:

“When you study a complex problem such as crater formation, a key challenge is the number of variables you have to consider. DiRAC’s computing services allow researchers to reduce the “time-to-science” - the time it takes to make a breakthrough – by providing access to both the computers themselves and technical support teams who give guidance on how to use them.”

 “To date, DiRAC has provided about 2 million core hours of computing time to this project and it’s great to see that they have already made such exciting new discoveries.”

The DiRAC Data Intensive Service based at the University of Leicester provided the research team with access to the scale of computing they needed to carry out almost 300 detailed 3D simulations, some of which took several weeks to complete. Access to DiRAC resources dramatically reduced the time taken for the team to take the project from its initial stages to a detailed picture of the Chicxulub event.

As a result of the research, all things being equal, a collision a few minutes earlier or later might have meant that the dinosaurs would have survived.  But the angle of collision shown means that the collision caused the maximum negative effect possible, unleashing an incredible amount of climate-changing gases into the atmosphere, triggering a chain of events that led to the mass extinction. The results were published yesterday in Nature Communications.

Further information

DiRAC High Performance Computing facility

DiRAC stands for Distributed Research Using Advanced Computing. The DiRAC High Performance Computing facility provides cutting-edge supercomputing resources for UK researchers working on world-leading scientific calculations across a wide range of areas including particle physics, astrophysics, cosmology and nuclear physics. It comprises supercomputers at Cambridge, Durham, Leicester and Edinburgh, each designed to support specific types of calculations.  DiRAC also provides access to a team of expert research software engineers to help researchers make the most efficient use of the available computing resources. https://dirac.ac.uk/

Figure 1: Shown are cross-sections through the numerical simulation along the plane of trajectory, with x =0 defined at the crater centre (measured at the pre-impact level; z =0); the direction of impact is from right to left. The upper 3 km of the pre-impacttarget, corresponding to the average thickness of sedimentary rocks at Chicxulub, is tracked bytracer particles (sandy brown). Deformation in the crust (mid-grey) and upper mantle (dark grey) is depicted by a grid of tracer particles (black).Tracer particles within the peak-ring material are highlighted based on the peak shock pressure recorded (white–blue colour scale); melted targetmaterial (>60 GPa) is highlighted in red.