Launchspace is asking for suggestions on how to clean up space trash, a topic which I had written about previously. So, if you have any ideas on how to begin to alleviate this serious problem, be sure to visit the above links and send them in. Launchspace may want to consider prizes for winning ideas, perhaps a trip to the space station or something. But so far, I have seen no mention of that. Still, the undeniable pleasure of seeing them run with your idea should be reward enough, shouldn’t it?
To illustrate how dangerous this is, imagine the proverbial screw loose. For the sake of this back of the envelope calculation, we’ll assume the mass is about 1g. By equating centripetal acceleration to the gravitational force divided by the mass, we can calculate the velocity at any given height, as v = sqrt(GM/r), where G is the universal gravitation constant, M is the mass of the earth , and r is the distance from the center of mass of the earth to that of the object, and sqrt means to take the square root of the paranthetically enclosed quantity. I’ll assuming a distance to the international space station, which is about 350Km. Given that, I get a velocity 7696 meters/second. That works out to 17,216 mph. For our loose screw (and neglecting rotational energy), that’s about 2961 Joules of energy, which is equivalent to a 2000Kg car moving 4 mph. You know how when you are driving behind a truck on the highway and your windshield gets hit by one of those little rocks? That, in contrast, going maybe on the order of only 40-60 mph. If this hits a satellite (or worse, an astronaut), it is going to be worse than a cracked windshield. Now assume the collision is inelastic, meaning it just doesn’t ricochet off. That 2961 Joules of energy is going to go somewhere, and it is not going to be pretty for whatever it hits. Granted, we haven’t taken relative velocities into account, but we are not guarantied to be moving in the same direction anyway.
So, as you get to work on your solution, these are a few of things you should be keeping in mind. Let’s save space by cleaning up space debris.