Peter Brown studies space rocks to help us understand what happens when they collide with Earth.

He has his eyes on the billions of rocks that hurtle around the infinite sky above us.  

Peter, a professor of physics and astronomy and Canada Research Chair in Meteor Astronomy, is especially interested in what happens when those rocks burst through Earth’s atmosphere. His team at Western University plays a key role in a global effort to analyze their dynamics and impacts and to share that information with space agencies such as NASA.  

“We take measurements that feed into models developed by NASA and the European Space Agency. We also help build those models.”

The story of a meteor strike begins long before a rock reaches Earth. Between Mars and Jupiter there’s a mass of asteroids, objects of various sizes that hurtle around the Asteroid Belt. Occasionally, these asteroids collide, breaking into meteorites. Some of those meteors drive through the Earth’s atmosphere. We see them as shooting stars. Most explode in the sky. Some, however, break up and the pieces crash to the ground.  

Perhaps the best known is the massive asteroid that made it through the atmosphere unbroken, striking what is now the Yucatán Peninsula in Mexico and obliterating most dinosaur species 66 million years ago.  

More recently, a meteor exploded over the city of Chelybrinsk, Russia on February 15, 2013. The blast produced a sonic boom that shattered thousands of windows and damaged buildings.  

To Peter, it’s events like this, and the many smaller meteors that reach the ground, that provide valuable opportunities for him and his team to use sophisticated cameras and microphones to analyze what has happened.  

“A lot of my work focuses on shockwaves that come from these events. I'm very interested in how they are formed and evolve and how the energy from the shockwaves impacts Earth.”

Agencies like NASA use Peter’s analysis to develop models for disaster planning.

“Depending on whether a rock lands in the ocean, a fairly populated area or a desert, our data can help determine what kind of emergency plan is needed. These events don’t happen often, but it's still important to be prepared. The dinosaurs didn’t have an emergency plan.”  

Peter’s fascination with space began when he was a child.  

“I became interested in meteorites at a very young age. They help tell us how the solar system formed. Now that I am a scientist, how cool is to be able to hold a piece of space in your hand, do the analysis and understand where it comes from?”

Much of Peter’s research involves students and seeing their enthusiasm is one of the highlights of his work.  

“There are a lot of students who are really very passionate about space. It's great to be able to get them involved in projects and see their excitement about discoveries they're able to make. I find that motivating.”

And he’s grateful for the opportunity to contribute to global safety.

“There's a fundamental part of the research we do which is driven by curiosity. But that curiosity takes on a whole new level of meaning when the work can influence government policy and the information we use every day to protect society. The fact our research contributes to the models and planning used in planetary defence gives that curiosity a real-world purpose.”