Sixty-five million years ago, a catastrophic impact forever changed the environmental landscape of Earth – and there was no way to see it coming.

This Earth-bound asteroid – or maybe several – changed the course of millions of years of evolution, altered the composition of our atmosphere – and the geology of Central America for good measure.

To prevent a similar event, we need to be prepared. Megan Bruck Syal, postdoctoral researcher at the Lawrence Livermore National Laboratory, works on the Asteroid Impact and Deflection Assessment (Aida) – which, for the first time, will test how effective a kinetic impact mission would be in altering the course of an Earth-bound asteroid.

“It’s not a matter of if an asteroid will impact again, but when,” says Bruck Syal. “Planetary defence began to be an issue when more and more near-Earth asteroids began to be discovered.”

She warns of close calls, like the Chelyabinsk meteorite – which in 2013 made international headlines when it left hundreds of people injured and damaged thousands of buildings in Russia. “It really captured the world’s attention because no one saw it coming. And it was pretty small yet it still did a lot of damage for its size.”

In the video above, Bruck Syal shows us how research into the structure of meteorites can inform us about the best way to redirect asteroids that could potentially be on a collision-course with Earth. “There’s a lot of unanswered questions Aida will lend insight to,” says Bruck Syal. “It’s essential to help future generations if they need to use this technology for real.”

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