MIT researchers have developed a way to map an asteroid’s internal structure, or density distribution, by analyzing how the asteroid’s rotation changes as it hits close contact with heavier objects like Earth. The technique could improve the goal of future missions to deflect an asteroid toward us, as demonstrated during NASA’s Dual Asteroid Redirection Test in September.
Knowing what’s inside an asteroid can help scientists plan the most effective defense. “If you know the density distribution of the asteroid, you can hit it at the right spot to move it away,” said Jack Dinsmore ’22, co-author of the study. paper about this work with Julien de Wit, PhD ’14, assistant professor in the Department of Earth, Atmospheric and Planetary Sciences.
“It’s similar to how you tell a raw egg from a hard-boiled egg,” says de Wit. “If you spin the egg, the egg will react and spin differently depending on its internal properties. The same goes for an asteroid during a close encounter.”
The team is eager to apply this method to Apophis, a near-Earth asteroid that could pose a significant hazard if it makes an impact. Scientists had ruled out the possibility of a collision for at least a century, but after that, their predictions turned pale.
