HomeScienceOpen Thread Thursday ©2015 Black & Right February 3, 2011 Science, Technology 5 Comments Space so full of junk that a satellite collision could destroy communications on Earth Is this a legit fear or more doom-and-gloom? The Machine Sorry, would not work, Mauser. You can’t apply the things you see happening on Earth to the way things happen in space. http://mauser.livejournal.com Mauser I once though of orbiting a gigantic block of aerogel or a gigantic sheet of mylar to “Sweep” an orbital path. It might not stop all the junk, but might change its energy enough to de-orbit it. Igor No, ‘twouldn’t work. Orbital mechanics, again. More specifically, momentum. Now, invent a tractor beam and you are gonna own the orbits… Igor Igor Guys, I was working in GEODSS from ’04-’05, and even back then we had a HELLUVA lot of junk up there, over 23K “objects” (we track not just satellites, but EVERYthing in orbit). There’s a buttload of crap up there, it’s getting more difficult to throw something up there without having to plot your orbit through all the debris and figuring out if the relative velocity of something that hits you is going to ping, ding, or destroy you due to simple object momentum. In other words, a collision with something that may kill your spacecraft. Or slap your booster(s) sideways. You get the idea. Wanna see JUST the satellites? Go to j-track 3D: Hmpf, looks like NASA no longer maintains the site! Pity, it let you see EVERY (non-classified) satellite in orbit. The stuff we had at GEODSS showed *everything* in orbit, because you want to track that stuff regardless of it’s function. It was interesting to see the geosync stuff, as well as the GPS birds in their orbits. LEO looked like bugs around a lite at night… MOST of these birds are nowhere near the “space junk” since if you want to go into geosync or GPS orbits you have to inject into LEO and then use another stage to control the burn to get to a HEO (which takes more energy…). Orbital mechanics, don’cha know… So, Chicken Little, the sky is NOT falling, but there’s a helluva lotta junk up there. If you can find a cheap/efficient way to deorbit all that crap, you’re gonna make a mint!! And if we could get the Chinese to quit leaving all their crap all over the place every time they launch, the picture would be a lot less cluttered. We were guilty of the problem in the 60’s, but “cleaned up our act” early on. P.S. – most of the orbits are all going in (mostly) the same direction – it’s not unusual to get a satellite to be pinged by other orbital garbage, it’s the relative velocity that kills… See the definition of a “kinetic kill”. Igor The Machine Every other so-called “news” story incants the, “Its-the-End-of-the-World-As-We-Know-It” theme. Or, as I like to call the nightly news hour, “The Scare the Bejesus out of Grandma Show”… Education. Learning. Because the More You Know, the less you have to depend on the vile and idiotic incantations of liars.