Asri-unix.647 net.space utzoo!decvax!duke!chico!harpo!mhtsa!eagle!ihnss!ucbvax!menlo70!sri-unix!REM@MIT-MC Tue Jan 26 21:25:15 1982 Collisions with skinny skyhook From: Robert Elton Maas Sigh. Because a skyhook travels at non-orbital velocity everywhere except at its center (geosync for fixed hook, LEO for spinning hook), it sweeps out a volume of space, coliding with native material at near orbital velocities, unlike normal small orbiting objects which bump into other orbiting objects only at perturbation velocities which are a couple orders of magnitude less than orbital velocities. Thus skyhooks have much greater problems, even in absense of manmade orbiting projectiles, than small orbiting satellites do. Does that make skyhooks impractical, after all there will always be a rain of new cosmic debris drifting into Earth orbit to replenish any area that we sweep clean?