What’s in an asteroid | MIT Technology Review

MIT researchers have developed a way to map an asteroid’s interior structure, or density distribution, by analyzing how the asteroid’s rotation changes when it makes close encounters with more massive objects like Earth. The technique could improve the aim of future missions to deflect an asteroid heading our way, as NASA’s Double Asteroid Redirection Test demonstrated in September.

Knowing what’s inside an asteroid could help scientists plan the most effective defense. “If you know the density distribution of the asteroid, you could hit it in the right place to make it actually move away,” says Jack Dinsmore ’22, co-author of the paper on this work with Julien de Wit. , PhD ’14, an assistant professor in the Department of Earth, Atmospheric and Planetary Sciences.

“It’s similar to how you can tell the difference between a raw egg and a boiled egg,” de Wit explains. “If you spin the egg, the egg reacts and spins differently depending on its inner properties. The same goes for an asteroid in a close encounter.

The team is eager to apply the method to Apophis, a near-Earth asteroid that could pose significant danger if it were to impact. Scientists have ruled out the likelihood of a collision for at least a century, but beyond that their predictions become hazy.