We can stop the space apocalypse with paintballs

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SALT LAKE CITY — Every 10,000 years or so, the black void of space spits something at Earth that devastates the planet and causes massive disruption to the normal order of things. But humans — with all our combined intelligence, resourcefulness and concern — have finally invented a way to prevent this kind of life-shattering space apocalypse from occurring: Paintball.

Sung Wook Paek, a graduate student in astronautics at MIT thinks that if a spacecraft at close range shoots two volleys of bright white paintballs at an asteroid, the combined effect of being bumped by the shots and a change in the reflective of the surface should be enough to move the object off track.

Why white paint? Every surface in space has an albedo, or reflectivity. It determines how much light gets absorbed and how much is reflected.

Even though the suns rays don't have a lot of energy, the combined effect of all those photons bouncing of a surface instead of being absorbed by it over a long period of time could move an asteroid off its course.

This radar image shows 4179 Toutatis, a nearth earth asteroid that could impact Earth in roughly 600 years.

If you turn an asteroid from a dark rock into a bright white surface, the whole equation of its orbit changes. So you cover the asteroid in five tons of white paint and artificially change the albedo.

Sung Wook Paek came up with the idea for the 2012 Move an Asteroid competition, a UN sponsored challenge to find the best way to bump a near-earth asteroid off its course. And he didn't just deal in the abstract. He used the asteroid Apophis, an asteroid that for a time was considered to have a significant chance of colliding with Earth. Now, it's got a 1 in 250,000 chance of a collision in 2036.

That the possible collission would occur so far away is good because this method takes a lot of time. In the case of Apophis, it would take 20 years for the effects to add up.

There are roughly 1300 potentially hazardous asteroids that have been identified as well as about 90 comets, all of which have some small possibility raining apocalyptic woe upon the world. So it's important to have a lot of tools in the tool box for how to deal with a threat.

Other methods include using rockets to knock an object off course, detonating a nuclear bomb on the surface, or using a gravity tractor, which would use the gravity of a spaceraft to pull the asteroid out of a collision orbit.