Matthias Meschede, a University of Munich student in collaboration with a team at Princeton University, has developed a first of its kind meteorite impact model. Unlike previous models which treated Earth as a perfect sphere with the impacting meteor as a point source, this one takes into account ellipsoidal earth shape and equatorial bulge while also allowing for a spatially distributed impact source.
“We have developed the first model to account for how the Earth’s surface features and shape would influence the spread of seismic activity following a meteorite impact,” Meschede said in a news release about the research. “For the Earth, these calculations are usually made using a smooth, perfect sphere model, but we found that the surface features of a planet or a moon have a huge effect on the aftershock a large meteorite will have, so it’s extremely important to take those into account.”
The research, published in Geophysical Journal International earlier this year, included a case study of the Chicxulub impact crater located off the coast of the Yucatan Penninsula and commonly thought to have wiped out the dinosaurs. The model shows that the non-spherical geometry serves to partially dampen seismic waves, reducing expected destruction predicted from previous models.
According to NASA’s Near Earth Object Program, which tracks objects with the potential to impact Earth within the next 100 years, an asteroid larger than 1 km can be expected to impact the Earth on average every few hundred thousand years. An impactor of this size could cause global disasters, including acid rain, partial sunlight blocking, and firestorms from the heated debris. There are several programs now focusing on how to deflect such an object once it has been discovered, preventing such a devastating collision.
The video below illustrates a possible sequence of events that followed the impact which created the Chicxulub crater.