With our Technology, Why could we not destroy any oncoming asteroids????

Answer 1

Because despite all the movies that depict technology and advancements, science in real life is no where near that advanced. It sucks, but we just aren't up to par.

Answer 2

Destroying an asteroid is tough as discussed by other responses. First, asteroids can be huge and our explosives, deadly to humans as they are, just don't produce a large enough bang to completely pulverize any of the larger asteroids. Second, asteroids are often made of materials which will cause an explosion to crack them into pieces with somewhat unpredictable trajectories rather than deflect the whole body itself. We don't have the technology for a weapon to then track the pieces and then automatically continue to go after stuff that is large enough to cause damage. Which is not to say that we won't try all of these things if an impact were about to happen.

A better option might be to detect an impending collision, and then try to push the asteroid out of a collision course. If detection happens soon enough, there is time for extended application of force and slight angle changes which translate into a safe miss by several thousand miles. So, both early detection and the ability to do something about it are important. If we knew that there was going to be an impact 100 years from now, we would likely develop technologies to prevent it. If it was going to happen next week, well, different choices would apply.

There is another aspect at work here. Human economy still isn't large enough to afford extensive planet-defense systems. Space science is in its infancy, and our ability to work in deep space is very limited.

That the probability of a hit in the near future is small is easy to demonstrate with a small comparison. The last suspected extinction level impact was 65 million years ago (the Cretaceous–Tertiary or K-T event). Modern humans have been around for about 40,000 years. We've only really known about the K-T event since 1980. It's still sinking into the collective human consciousness. Give it a few more decades - I suspect we'll build the defences.

Answer 3

Destroying a threatening asteroid is unnecessary and undesirable because well just get hit by the debris, which can cause even more damage. 100 one megaton explosions cause 10 times the damage as one 100 megaton explosion, for example. It would require far less energy to simply nudge it off its collision course. Small funds are being investigate to track earth orbit crossing asteroids to give us time to do something should it be needed.

Standard risk analysis cost-benefit analysis proceedures widely used by insurance companies shows that investment in countermeasures should be much greater, but politicians are more concerned with voters' concerns than their stewardship responsibilities. Right now, planetary defense rates three notches below Rudy's family life and the sincerity of Hillary's cackle.

Answer 4

Using a quote from 'Armageddon':

President: We didn't see this thing coming?
Dan: Well, our object collison budget's about a million dollars. That allows us to track about 3% of the sky, and beg'n your pardon sir, but it's a big-*** sky.

If we were able see a asteriod far enough away, our biggest nukes might be able to slighty change the projectory of the asteriod. Kind of like shooting a BB at a bowling ball that is rolling towards you.

Plus there is a much greater chance that we will destroy our own planet before we get hit by another asteriod. So not much money is spent on destroying asteriods.

Answer 5

These objects often have very high velocities and are extremely large. They can be miles across and move at 100 miles per second. Thus .5mv^2 is huge. We would have to accomplish a direct hit with a very powerful explosive, likely nuclear. Launching such devices is risky and would require cooperation likely taking weeks to arrange. If we saw it in time, if we had several missles ready, if we hit it, and if we didn't precipitate a nuclear exchange by the launch, we might survive.

Answer 6

some asteroids are huge. destroying one that is on a collision course is not a good strategy because the debris would still collide with earth and could do just as much damage. what they seek to do is to make it change its course and miss earth.

Answer 7

If we had such a technology, we would be able to destroy our planet and the moon completely and sink it into the ocean.