Space & Astronomy

Asteroids are harder to shatter than we thought

By T.K. Randall
March 4, 2019

Image: AI-generated (Midjourney) Exactly what we should do to stop a large incoming asteroid has long remained a topic of debate among physicists. One possibility - which would be to try blowing it to pieces - relies on accurately calculating just how much energy it would take to disintegrate it entirely.

Around 20 years ago, researchers used a computer model to determine that a 25km-wide asteroid would be completely shattered if it were struck by a 1km-wide asteroid traveling at around 11,000mph.

Now though, revised computer models have cast doubt on this conclusion and have instead indicated that such a collision would still leave behind an intact core with a sufficient enough gravitational pull to attract the remaining fragments back towards it.

"We used to believe that the larger the object, the more easily it would break, because bigger objects are more likely to have flaws," said mechanical engineer Charles El Mir of Johns Hopkins University."Our findings, however, show that asteroids are stronger than we used to think and require more energy to be completely shattered."

This begs the question - just what should we do to neutralize an incoming asteroid ?

"It may sound like science fiction, but a great deal of research considers asteroid collisions," said El Mir. "For example, if there's an asteroid coming at Earth, are we better off breaking it into small pieces, or nudging it to go a different direction ?"

"And if the latter, how much force should we hit it with to move it away without causing it to break ?"

"These are actual questions under consideration."

Source: Astronomy Now

Tags: Asteroid