why does blowing up an asteroid do no good?

Question

the earth is protected against being cratored by impacts because objects burn in the atmosphere. so my thought is that if you break up the object before impact with the surface you expose more suface area to heating thus more burns up before striking the eath thus less damage is done. I have heard countless experts say that breaking up an asteroid before impact does little. why am i wrong?

Answer 1

Blowing up an asteriod whos orbit is crossing earth's path will not change the asteriod's orbit. It will still remain travelling along the same path to hit the earth with the same speed, just with more pieces. Unless the explosion is large enough to leave only small pieces of rock (small enough to burn up in the atomosphere) you are left with several smaller asteroids which will still strike the earth with major destructive force. Therein lies the problem.

Answer 2

At first glance that seems logical. However, scientists have learned by using computer models that blowing up an asteroid not only would not work--it might make an impact wors.

Here's why: any asteroid we'd need to stop would be large. Now, if you blow it up, some of the mass of the asteroid will be pulberized--and those little pieces will burn up in the atmosphere. But mosst of the asteroid would be broken up into chuncks that would still be big enough to get through the atmosphere and do a lot of damage. Even worse, there'd be several of them. So it would be like a shotgun blast instead of a single bullet--the damage could be even more widespread than if you did nothing.

Fortunately, there's another way to stop an asteroid impact--divert it into a slightly different orbit. Take the asteroid that's supposed to come very close in 2036--so close that it theoritically could hit (scientists think its unlikely--but can't be sure yet).

If we have a spacraft intercept the asteroid a couple of years before that (we'll know by then if it is a danger) they can use a variety of techniques to nudge it--not very much, because its very massive. But it wouldn't take much of a chnange--because the change would have a couple of years to build up, shifting the asteroidd's course enough to miss.

Of course, if we don't get serious about developing advanced spacecraft, and that asteroid (or another one we don't even know of yet) does turn out to be dangerous, we'll be out of luck.

Answer 3

You are right, if you blow an asteroid to smaller pieces, chances are those pieces will burn in the athmosphere. But to reduce a mile long asteroid to little asteroids, you need a lot of energy(and a mile long asteroid is small compared to others that are out there). A nuke on it's surface will probably just crack it. So it's just not possible with our current technology.

On the other hand, deflecting it is a better option. If we detect the asteroid long before it hits Earth, a slight change in course will propbably save us. To do that slight change in course we don't need that much energy, in fact, if we could send some sort of satellite to fly next to it, the gravitational force from the satellite could probably do the job. Or if you like explosions, yes, lets nuke it on one of it's sides and hope the force is strong enough to divert it.

Answer 4

The explosion would only make the asteroid into a bunch of big fragments that would still be able to impact Earth. So basically you're destroying several parts of Earth instead of having just one large impact. The best method is to simply move the asteroid onto a different course.

Answer 5

asteroids are made of rock after all, only covered with a little ice and dust maybe...

when you blast an asteroid, like other forms of granite, it's gonna break into little pieces and fly around...however the surface area becomes wider due to the impact of the blast. however because they are already caught in the gravitational pull, they dont go off course, they might move out a little...and now that the mini-rocks are more spread out, the danger area has become wider and more areas will be affected...so not exactly a good way...

Answer 6

The objects capable of causing huge devastation are absolutely huge. We're talking things kilometres in size. We have no way to blast something that large into small enough fragments to significantly reduce the risk. You'll just get a few smaller ones, each of which is still large enough to do a colossal amount of damage on impact.

The best course of action is to find some way to divert the course of the asteroid, rather than trying to destroy it outright.

Answer 7

if you blew up an asteroid shortly before it hit earth then the fragments would still slam into earth with all of the force of the original asteroid. just instead of a localized crater you would end up with a good portion of the atmosphere getting blown off because of all the tiny fragments. basically the atmosphere rather than the ground would absorb the brunt of the impact, and our atmosphere is more fragile than the ground is.

if they can't move the asteroid into a safer orbit before it hits us its better to just let it hit us, contrary to what hollywood might have to say.

Answer 8

According to newtons law, "blowing up" an asteriod would do no good because the remains of it would still be able to keep going and hit whatever is in their course.

Answer 9

Because if you blow it up there may still be pieces large enough to hit the Earth, and I would rather worry about one hit than many hits