Armageddon Asteroid

It is not a matter of ‘if an asteroid hits Earth’, but ‘when an asteroid hits Earth’.

Someday an asteroid, probably a fairly large one capable of mass destruction, will hit Earth. Thinking positively, we will have detected this “extinction-level” asteroid 25 years before it hits Earth. With this much time to act, my plan to save Earth would be to use a kinetic impactor. The kinetic impactor will be propelled into the asteroid with a great amount of force, enough to change its course so that it will not obliterate Earth.

Say, the asteroid is 110 km and traveling at the speed of 75km/s (NASA says the average speed of an asteroid is 25 km/s, so I tripled it)

The force necessary to knock the asteroid off course can be found using the formula:

Force  = Mass ·  Acceleration. However, I first need to find the mass of the asteroid using the formula: Mass = density · volume.

Assuming that the meteor is spherical, I can find the volume of the asteroid by using the formula: V = ⁴⁄₃πr³, after plugging in 55km for the radius…volume = 6.97×105 km3

Assuming the density of the asteroid is 210 kg/km3 , mass =  210 · 6.97×105 = 146,370,000 kg

To find the force necessary, all I need to do is plug 146,370,000 kg and 75km/s into the formula: Force  = 146,370,000 kg · 75km/s.

A force of 1.097E10 N or greater is required to knock this particular asteroid off course using the kinetic impactor.