I see that today, the inhabitants of the space station had to make a run for it and hide out in the Russian space shuttle for a while until a newly discovered piece of space junk whizzed by. Someone said something to the effect that “they’re going to have to do something about all this debris pretty soon,” particularly since that collision last month, I imagine. But, what could “they” do? At 5 or 6 mps, you can’t just put up a screen and catch the stuff. How can all these orbits be swept of all that material? And what about all the little screws and screwdrivers and pieces of detritus that are also traveling at that speed? How can any of it be eliminated? What are some ideas that are being floated, so to speak?
Presuming that a lot of it is magnetic, you could put some super-powerful magnets up in orbit on certain trajectories, and then put all of your satellites and space stations and stuff on the same orbits as the magnets–sort of like a guy running interference up ahead.
EDIT: Woops, didn’t realise this was GQ. No idea what all plans might be being floated.
What I dont understand is how they can detect pieces of space junk less than a half inch diameter, hundreds of miles away from the space station. And why there isn’t more little bits like that to be concerned about.
You are talking about what is increasingly commonly coming to be known as Kessler Syndrome.
There aren’t a lot of answers at the moment. One idea is a powerful laser that can push objects into a more eccentric orbit, causing them to reenter earth’s atmosphere and burn up. I’ve also heard about a big sponge-type idea we could put in orbit that would allow objects to hit it and “absorb” them, then let that burn up on reentry, too.
Smarter people will be along shortly.
If and when one these smarter people happens along, could they please also explain something that’s been driving me crazy ever since I heard of this problem—namely, why is this happening? Shouldn’t all this stuff be moving in the same direction? Aren’t all rockets launched in the direction of the Earth’s rotation? And to further compound my confusion, space is just so damned BIG—even if a million monkeys typed for a million years, how the hell are these things crossing paths? OK, I can partially figure out the answer to the second question. I know that there are ‘premium’ orbits for satellites. You don’t just shoot them up there in any old random orbit. They’re clustered like ships in the same shipping lane. I get that—but still, how do they find each other? It still seems like it should be a damnably improbable occurrence.
The cheapest orbit to launch into (and therefore the one that has the most stuff in it) is one that’s inclined by the same amount as the latitude of your launch site. Cape Canaveral is at about 28.5 degrees, so there’s a lot of stuff in an orbit that’s inclined by 28.5 degrees off the ecliptic. But there are many such orbits, inclined in different directions, and which one you end up in depends on when you launch. So everything’s moving more or less east, but some things are moving as much as 28.5 degrees north of east, and some are moving 28.5 degrees south of east, so you can get side-on collisions. And orbital speeds are fast enough, and 57 degrees a large enough angle, that the relative velocity is still pretty big.
For a visual demonstration, take a look at NASA’s JTrack3D. It is indeed quite improbable for there to be a collision, and the recent one was the first of it’s kind. But there are tens of thousands of other objects we’ve left up there too. Space may be big, but low earth orbit is a comparatively limited expanse of it.
And any time an astronaut loses a bag-o-tools, or a pair of pliers, etc., that material moves away at an angle and occupies a different orbit. Enough miscellaneous dropped screws, tools, ejecta, etc. combined with the remains of boosters, etc. makes for a lot of junk in many different orbits, any of which can puncture a spacecraft or a space suit if hit at any appreciable angle. So I’m waiting here to see if someone actually has advanced any reasonable solution yet.
And the primary launch site of the Soviet/Russian space program is at Baikonur, which is 46 degrees latitude. And if you launch two satellites from there 12 hours apart, the two orbits will be almost perpendicular to each other.
Also a fairly large family of satellites are launched into polar orbit. Basically any satellite that needs to see all areas of the earth, for scientific observations or military reconnaissance. And also communication satellite networks designed for global coverage, e.g. GPS and Iridium.
I know that there is pressure for better designs that minimize space debris. Certain low orbits deteriorate faster; if we didn’t mind replacing satellites more often, we’d prevent debris accumulation by putting them there. Some of the debris is paint - little chips can break off and still do some sizable damage - so one proposal is to stop painting flags on everything. There are other protocols, such as returning all trash back to Earth and being better about tying everything down (such as tools).
To my knowledge, there are no serious proposals to eliminate what’s already up there - just a few sci-fi type ideas that might work given the right tech and enough money.
I believe very little of it is magnetic: iron and steel is very heavy, so only light-weight-but-strong materials are sent up, I assume the bulk of the metals are alloys of aluminum, magnesium, and titanium. This dosen’t even include non-metallics, like insulation and paint flecks. I believe a few years ago one of the space shuttles windows were chipped by a fleck of paint impacting with the punch of a rifle bullet!
All true, of course, but I was trying to keep it to the simplest case.
There have been discussions of how to scrub out orbital space debris. Back during the days of SDI they were anticipating putting vast constellations of hardware into orbit (which, of course, they didn’t want to get hit), and if you look in the literature of that you’ll find some proposals. I know that science fiction authors writing about Space Elevator “beanstalks” have spoken of the need to clean out the orbits (as Arthur C. Clarke does in The Fountains of Paradise), so it wouldn’t surprise me to find the folks seriously pushing this technology now talking about it.
When I was working in Laser Propulsion some people were talking about using space=based lasers to help nudge space debris into lower orbits. Jerry Pournelle, IIRC, wrote about using “soft satellites” ant would allow space junk to strike them, burrow in, and get stuck – kinda like sending big styrofoam balls into space. But I don’t know if he based that on any firm studies.
Relevant brief article, for anybody who hasn’t already found it.