Slashdot Mirror
Air Bags for Planetary Defense
Gallowglass writes "The Canadian paper, the National Post, is reporting on a plan to divert asteroids headed towards Earth. According to the story, the proposer, a Dr. Hermann Burchard, suggests deploying an inflatable mylar bag a few kilometers in size, and using it to push the projectile aside. An air bag for earth? The deployment mechanism isn't detailed in the story."
I think the idea would be to make some attempt to match it's speed, then contact and start the engines firing to push it off course.
Rather than think of it like a car's air bag, think about it as a way to spread out the pressure along the surface of the object. A rocket on the surface of a comet or loosely bound asteroid may just disintegrate the parts, yielding little benefit.
Which is more comfortable to sleep on: a pillow or the blunt end of a pencil?
Two Things-
First I think the idea is to nudge the asteroid to the side and deflect its past, not get in front of it and have the asteroid bounce off.
Second, to accomplish this the ballon needs to bedeployed while the asteroid is still far away from earth. That will give it time to gently push it into a trajectory that doesnt collide with earth.
And what is wrong with breaking it up? Say you hit the asteroid with the biggest nuke we've got, wouldn't it either a) break it up into smaller pieces that would then hit the atmosphere and burn up, or b) shatter like a clay-pigon and the pieces would miss the Earth?