Asteroids that could threaten humans on the ground — and indeed, all of human life on Earth — are a very real threat, even though the odds of such a thing happening remain slim. And now, according to The Express, getting rid of them in time may be harder than previously thought.
For billions of years, the Earth’s primary means of protection against deadly asteroid impacts has been the atmosphere. Incoming asteroids either burn up due to friction with the atmosphere, or skip off the atmosphere — not unlike how a rock is skipped across a placid lake.
But some still get through. In fact, the Earth is littered with asteroid craters. Indeed, 65 million years ago, the K-T event — in which an asteroid struck what is now the Yucatan Peninsula — wiped out the dinosaurs. Similarly, just a few years ago an asteroid exploded over a populated area — Chelyabinsk, Russia, a city of over a million people — causing hundreds of injuries.
So how can the space community get rid of an asteroid before it threatens us all? In a word, it can’t. But they’ve been working on it.
Blast it or deflect it?
There are two potential ways of getting rid of a deadly asteroid. As of this writing, no space agency or private organization currently has a reliable means of deploying either of these methods, however.
It buzzed past us about three hours ago. Read more here: https://t.co/AoADPwTGsi
— UberFacts (@UberFacts) March 5, 2019
One possible way of getting rid of such an asteroid is to smash it to smithereens, but there’s a flaw in that plan. If you have a million tons of asteroid headed your way, and you blast it, you still have a million tons of asteroid headed your way. Only now it’s billions of smaller pieces spread over a wider area. The Earth will still experience the full impact of the asteroid, save for any chunks that are blasted into a trajectory away from Earth.
Which brings up the second plan — one currently favored by the space community — using rockets to deflect it. The theory goes that a spacecraft could be sent to the rock, attach itself, and then its rocket engines could fire, pushing the asteroid into a trajectory away from Earth. Per The Inquisitr, NASA is testing that very method, currently sending the DART craft to an asteroid, one which is not threatening the planet, to see if it can be deflected away.
Unfortunately, both of those plans are easier said than done, according to new research by Johns Hopkins University.
The science is rather tricky to explain, but basically computer simulations showed that an asteroid could begin to crack and break up within microseconds of a spacecraft — or a weapon — touching its surface. What’s more, in order to blow it apart enough to neutralize it, it would basically have to be vaporized. Otherwise, all of the fragments will simply be held together by the rock’s own gravity, and indeed, parts of it may even re-form into larger parts.
Similarly, deflecting an asteroid could prove more difficult for the same reason. Any attempt to deflect an asteroid artificially would require the deftest of deft touches by whatever spacecraft lands on it in order to avoid shattering it.
Lead researcher Charles El Mir says that — should the day come when the space community has to deploy a craft to neutralize an asteroid — all possible outcomes should be looked at.
“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.”
The team’s research has implications beyond just protecting life on Earth, however. Already some private industries are working on plans to mine asteroids for minerals and precious metals, and those mining operations would do well to consider the literal impact of whatever craft they send up, says El Mir.