DARPA wants plans to recycle old GEO sats

https://www.networkworld.com/community/ ... s-new-life

I am all for recycling but i wonder if somebody has put something up there that does not quite confirm to international treaties and if a refuelling is attempted on an "accidentally" chosen wrong sat might it cause a cascade event ruining things for everybody. Or are bad cascade events something that is only likely to happen in lower orbits after all we can probably live without Sat TV but GPS going down might cause a bit of a traffic jam.

Naw. There's not much risk. Its all about the relative velocities. If you match orbits with something close enough to dock or capture it, you can bump into it without making too much of a mess. You can still tear them up like the accident where a Progress crashed into Mir, but its more like a fender bender instead of a train wreck.

What is dangerous are crossing orbits, either in plane, or eccentricity where the relative velocities and energies are high. Its the difference between two cars going 60 mph rubbing fenders as opposed to meeting head on.