Armageddon

Armageddon is an action movie with Bruce Willis which means it has to have perfect physics, well not quite, but it did pose an interesting question; What would we do if an asteroid was going to hit us? Well, NASA has you covered with a bunch of different techniques to prevent a true Armageddon.

First off, NASA is always on top of monitoring space to make sure that if an asteroid had a trajectory that would even come close to earth, they would investigate. To spot asteroids, many pictures are taken, more specifically, a few pictures are taken of a static shot of space a couple minutes apart, then a computer will scan for any moving objects. After an object is spotted the trajectory is calculated with the given data.

After that, there are many ways of dealing with an asteroid, but what I will be talking about is Asteroid Laser Ablation, which is basically shooting the asteroid with a really big laser. The whole purpose of the laser is to heat up part of the asteroid so hot that it turns to gas through the process of either sublimation or vaporization. When part of the asteroid has heated up sufficiently, the gas will shoot off into space, and due to Newton's Third Law, the rest of the asteroid will shoot in the other direction, which ends up changing the trajectory.