Tossed in Space
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Just in case you are an astronaut and need something to worry about, according to NASA there are 18,000 pieces of space junk the size of a basketball or larger right now orbiting the earth. That’s 18,000 chances to slam into the International Space Station (ISS), bump into a U.S. Space Shuttle, or plow into any of a number of satellites in low Earth orbit. Twice the ISS has had to be moved to avoid potential collisions and one other time when it couldn’t be moved the crew huddled in their Soyuz taxicab for danger to pass, with one such near-miss taking place just last week, which is what inspired this column.
I say it is time to clean up all that junk.
Space junk means everything from rocket upper stages weighing several tons down to the odd wrench lost in space by space-walking astro- or cosmonauts. This stuff that got to space more or less by accident is now torquing above the ionosphere at around 17,000 miles-per-hour, which would be worse if nearly all the junk wasn’t going in the the same direction. Friction and gravity will eventually bring all the space junk back to earth, but that could take centuries. So I say simply to avoid any more space junk stories in USA Today, we ought to find a way to get rid of the stuff.
It won’t be easy. We can’t shoot it down, because even if we are accurate enough to hit the junk all we are likely to accomplish is blasting it into lots more smaller pieces that will need tracking. We could shoot it with high-powered lasers, but unless we were able to vaporize the debris completely, all we’d be doing is boring very nice holes in it.
Nope, we have to gather the stuff and bring it back to Earth. But how?
I propose a space garbage scow.
My garbage scow would use a very fine net to capture the debris and hold it. The net could be built from kevlar, but this week I’m making everything from carbon nanotubes, thanks, so that’s what we’ll use. Nanotubes have the highest strength-to-weight ratio of any material and would allow us to make a very large, very light weight net. Our point here is to make the net light rather than strong, since our capture speeds will be low and the lack of gravity ought to make it easy to keep the junk tethered together. The point of making it strong, then, is so it can be light enough to be big enough to maybe gather all the junk — all 18,000 pieces — into a single scow.
I imagine a seine purse-style net, if you know your commercial fishing. Launch the net into an inclined polar orbit generally higher than the space junk to be harvested. The polar orbit will ensure that eventually the scow will go over every spot on the Earth as the planet rotates below, but it also means the scow will eventually cross the path of every piece of space junk.
Here’s where we need an algorithm and a honking big computer, because this is a 3-D geometry problem with more than 18,000 variables. Our algorithm determines the most efficient path to use for gathering all 18,000 pieces of space junk.
I haven’t yet derived this algorithm, but I have some idea what it would look like. We’d start in a high orbit, above the space junk, because we could trade that altitude for speed as needed, simply by flying lower, trading potential energy for kinetic.
Dragging the net behind a little unmanned spacecraft my idea would be to go past each piece of junk in such a way that it not only lodges permanently in the net, but that doing so adds kinetic energy (hitting at shallow angles to essentially tack like a sailboat off the debris). But wait, there’s more! You not only have to try to get energy from each encounter, it helps if — like in a game of billiards or pool — each encounter results in an effective ricochet sending the net in the proper trajectory for its next encounter. Rinse and repeat 18,000 times.
It won’t always be possible, of course, to gain energy from each encounter, but that’s why we start in a higher orbit, so as energy is inevitably lost it can be replenished by moving to a lower orbit.
By the same token I think we would logically start with smaller bits of space junk so the net would gain mass steadily over time, then do the same again at each lower altitude. Eventually the net would have corralled hundreds of tons of debris, carrying it down into the atmosphere where atmospheric friction would eventually burn it all up in a spectacular visual display that would create a thin ring of fire all around the Earth.
It’s a crazy idea, sure, but it could work. For all the worrying we do about space junk hitting astronauts or rockets as they launch, we could pretty easily get rid of it all. Small to big, high to low, all it would take is time. How much time? If the scow orbits every 90 minutes and it takes an average of a dozen orbits to set up the capture of each piece of space junk, that’s 18,000 * 90 * 12 = 19.4 million minutes or 36.9 years to get it all.
Funny, that’s about how long it took to put all that crap up there in the first place.
Let’s wait until we develop the ability to create a black hole. (My wife claims the credit for that solution.)
Random question. Where the heck is Nerd TV? If Nerd TV was a school project, Bob you would have failed that class miserably.
Use the mass driver described by Bob Phillips to deflect garbage orbits to earth, plus mount the mass driver on a 360 pivot, and use a computer to calculate the direction to fire the gun from to adjust the course of the garbagecannonship.
I hope somebody can build machines that awesome someday.
70th.
Cringely, I think you should stick to not knowing anything about the computer industry.
Not only is a multiple inch thick kevlar net capable of catching 15km/s space degree not going to be “fine”, but unless you are prepared to wait a million years for atmospheric drag to bring the net down from high orbit, you’re going to be using multiples of the nets mass as propellant to move it.
With 78,000-odd space particles entering our atmosphere each year, and 12,000-18,000-odd over 1kg in weight, many of which make it to the surface, the 18,000 pieces we’ve left up there seem uninteresting. The solar system is like your carpet after a bunch of tradespeople have been in your house to fix, repair, replace, your kitchen, bathroom, light fittings and balcony. It’s a mess of debris of all different shapes and sizes. From gasses to grains of sand, to pebbles, stones and basketballs. If you’re intention is to ‘clean up’ our little sector of space, forget it. It’s like sweeping the dirt.
“If you’re intention is to ‘clean up’ our little sector of space, forget it. It’s like sweeping the dirt.”
Which, funny enough, is what people used to do before the Victorians invented the grassy front yard.
Bob might have some of the details wrong: he’s not a rocket scientist, he’s a journalist.
But the problem is real. And shouldn’t we be glad that some people in the mainstream are getting it?
Great idea as a solution, but there are some glitches in the details.
One big detail is wrong – if the scow is in a polar orbit and most of the space junk is traveling in the same direction in equatorial orbit, these are not going to be low-velocity encounters. It’ll be two 17,000 mph objects hitting each other at a right angle. If the net is held open by a solid frame, you’ll need a carbon nanotube equivalent of bungee cord to absorb the impact without damaging the frame. Plus, after a few encounters, the net will have been deflected by the momentum it absorbs from the captured debris. At that point, it’ll no longer be in a polar orbit, but in a highly eccentric equatorial orbit. It’ll be cheaper to just launch the thing into an eccentric equatorial orbit in the first place.
Also, I don’t see this solution being practical from a manufacturing and cost perspective if it relies on the traditional NASA contracting process. Better to crowdsource the design and launch it from a private company. You might be able to get each of the various space agencies and private launch companies to fund the cost of a single capture net, so that you have about three or four of them up there.
Bob,
Don’t know if this would work or not but….. I dig it just for the Quark picture!
two things pop out at me right away that make your proposal is silly:
1. the amount of fuel needed would only allow you to visit a few pieces of debris
2. the kinetic energy of objects in orbit is greater then their mass in dynamite. There are some awesome pictures of aluminium bbs hitting test satellites in the lab.
the problem is difficult to wrap your head around at first. I think it is analogous to a road trip. you end up with enough dead butterflies on your car that you think it would be easy to catch them by dragging a net. get out of your car and go out on the side of that same road, you are not likely to see a butterfly let alone catch one.
now pretend like the butterflies explode if you touch them too fast and you can only take 10 steps before you die.
Yeah, right. Because magicium will enable it to avoid all those useful commercial and “black” military satellites out there now while still gathering up the 18K pieces. A honking big thruster would help with active steering, but you are still going to find the complexity and the funding more unobtainable than the carbon nanotube net. (what, no quantum nanotubes?)
Um, this time, it is rocket science, I’m afraid.
You can’t “trade potential energy for kinetic” in orbit. It takes energy to drop to a lower orbit, just like it takes energy to raise to a higher orbit. Tell, me, exactly, how you’ll “simply fly lower” in orbit? There’s only one way, reaction mass, which means fuel.
And the very idea that a polar orbit at right angles to the equatorial orbit that quite a lot of orbital debris lives in will result in “low capture speeds” boggles the mind.
Better idea: fire ions at each chunk of garbage until they’re so heavily ionized that they interact with the earth’s magnetic field in such a way as to be driven lower towards the atmosphere (charged particle + motion through magnetic field lines = force perpendicular to passage through field lines).
Or any of a dozen of other ideas that folks have probably already thought of.
A garbage scow, seriously? Have you been watching TV versions of space flight lately?
I think you have underestimated the speeds and energies involved. In low earth orbit velocities are on the order of 10 km/s. Picking up trash in an equatorial orbit with a spacecraft in polar orbit (at the same altitude) means that the approach speeds will be on the order of 14 km/s. Swooping down from high orbit to low orbit (even if orbits are coplanar) has similar problems.Falling, in an elliptical orbit, from 1000 kilometers to pickup trash at 300 kilometers gives a delta-v of almost 9 kilometers per second (this is the speed difference as the trash collector approaches the trash from behind). This is not feasible.
[...] ROBERT X. CRINGELY PROPOSES a space garbage scow to clean up orbital debris. [...]
See if that Oreck guy is willing to undertake a space program.
Wouldn’t two to four garbage scows to hold the net open be better? Or, better perhaps, once we have a space elevator in place we could build a space vacuum to suck the stuff back to earth in a hurry, just like siphoning gasoline. The net would lead to the siphon hose: the greater gravity on earth would suck the space junk down in a hurry.
How on earth can you vacuum inside a vacuum? You cannot “suck” anything out of space, there’s no air to suck.
And any kind of syphoning wouldn’t work either, you need a gravitational difference for that to work, like the volume of petrol in the longer end of the syphon tube weights more than the shorter end, the longer end falls, pulling in more petrol at the short end. You’d need a tube several hundred miles long at that altitude… But still, nothing to suck, so redundant theory anyway..
Good fun, although this is an absolute classic -Classic!- example of why Information Technology types (and curricula) need more physical sciences (or hands-on labor actually, y’know, building stuff). Physics – Its the Law!
On a more serious note, I’m attracted to a solution out there that involves using water to slow down the junk such that it deorbits. The hard part about cleaning up space so far seems to be getting past the ‘tragedy of the commons’ attitudes out there, but I think the marketplace, once again, holds the answer.
Heh, ‘Capitalism’. Is there anything it can’t do?
You really should have identified the ship picture. It’s from the 1977 TV show Quark which IMDB describes as, “The misadventures of an outer space garbage collector and his crew.”
http://www.imdb.com/title/tt0077066/
Bob, it’s a cute idea, but it has a problem. Consider, simplest case, a polar orbit for the net and an equatorial orbit for the random space bolt, both circular and (obviously) with the same altitude. Let v = the orbital velocity; then the relative velocity at impact will √2v or roughly 1.414v. For a relatively low earth orbit, that’s in the neighborhood of 11 kilometers/sec.
You won’t get a capture, you’ll get a bright flash and an expanding cloud of vapor and fragments. For small objects, that might be okay, but for larger pieces, you’ll get large fragments heading off in random orbits. This isn’t probably a net win.
As it were.
You also must not know the scrap metal business very well. Somebody paid through the nose to push that “junk” up the gravity well. Why would you spend as much again just to dump it back down? After going to all the trouble–and it will be a lot–to gather up all that high-tech stuff, you’d want to park it someplace stable, to re-use in future projects. It has resale value, and it’s already catalogued.
This is too important to trust to governments. What this planet needs is some good enterprising rag-and-bone men.
This is one of the best comments on here. Yet again, we can harness this beast called capitalism to solve a problem. If 18,000 items are in orbit, a combination of salvage (some enterprising person WILL do it eventually) and tagging each one with a ‘bounty’ could wipe out most of this problem. Larger items have their own worth in space while smaller ones could be assigned a bonus to sweeten the pot for anyone willing to deal with them.
Although the idea of hitting them with a solar powered laser in precisely the right spot that the out-gassing of vaporized material would propel them towards the atmosphere is pretty slick as well…
Actually, Bob, you _can_ use lasers to effectively de-orbit debris. By vaporizing minute amounts of a piece of debris at the right time, you can use the object’s own mass as reaction mass. In other words, you create a small ‘jet’ off the object by vaporizing a small part of it. You time things so that that jet is pointing in the right direction to lower the object’s orbit. Do this enough times, and the object will eventually get down into enough atmosphere to de-orbit.
The plot of the short-lived 1978 TV series “Quark” was about the so-named intergalactic garbage vessel and its Trek-parody crew, led by Captain Richard Benjamin. A must see!
There is an analogous an arguably more pressing garbage problem in the oceans. The waters in the central gyres contain vast amounts of tiny pieces of plastic. See e.g. the Wikipedia article http://en.wikipedia.org/wiki/Garbage_Patch . I’m sure bright ideas on how to clean that up would be welcome.
Even better idea, use those cool GLAD ForceFlex® Bags! They can hold anything!
“Ficus … I think I hear the bee …”
Andy Griffith already did this in 1979:
http://www.imdb.com/title/tt0079847/
Imagine a deep trash can filled with aerogel scooping up most of the small debris. The aerogel is probably radar transparent, so the ‘can’ leads the scow as it seeks out debris in an opportunistic fashion (minimal fuel consumption). This scow would still need fuel to reboost (every capture would steal momentum), so fuel and aerogel replacement requires in orbit support (ISS or fuel depot). The debris could be de-orbited by jettisoning the ‘can’ at perigee with a negative vector, the scow reboosting to rendevous with a station to connect to another ‘can’ to repeat ad infinitum.
Wasn’t there a show in the 70′s called Qaurk about this?
Or you could create highly ionized surfaces on orbiting orbs whose chief purpose is to attract this space junk as soon as a near pass by occurs. Left in space and powered by solar energy, these orbs will dutifully capture this junk over time without major cost or maintenance.
I accidentally came up with a solution to the space junk problem in the course of working on a combination rocket and laser transport system to reduce the cost of lifting a million tons per year to GEO for power satellite construction. It looks like this would get the cost per kg to under $100.
An ablation propulsion laser of only a few MW and a redirection mirror in GEO is enough to bring down hundreds of tons of space junk every year. One sized in the GW range for lifting parts to GEO would make very short work of cleaning up the space junk.
Google henson oil drum for more detail or ask, hkeithhenson@gmail.com
Keith Henson
There is a solution in nature. What we need is a small moon in low earth orbit. It will need enough mass to disrupt the junk from its present orbit.
It is believed the moon is getting farther and farther from the earth. At sometime in the very distant future it is believed the tides will be less, earth’s rotation about its axis will be less stable, and the climate will change.
Once my small moon cleans up the junk in orbit, maybe we can use it to adjust the moon’s orbit.
Where do you get a small moon? I haven’t seen them at the local hardware store.
Aisle 7, between plumbing and gravity generators.
Pay close attention to your plumber and he’ll eventually come up with a moon.
Make an inflateable one a la Bigelow Aerospace.
As a frame of reference consider the average height at which the 18,000 particles are orbiting. If it’s 1,000 miles then there is an average density of one-one-piece-of-junk-per-four-square-miles. That’s because the surface area of the sphere at such an orbit is equal to:
(4) times (Pi) times (Earth’s radius + Orbit Height)
Although it is difficult for non-specialists to know the average orbit height, we *do* know that geosynchronus communications satellites have orbits of 22,000 miles. Thus if all the junk is orbiting at that height then the average density is only one-item-per-18-square-miles.
Oooops! I have to correct my own comment owing to the error of failing to square the radius term.
The surface error of a sphere is:
(4) times (Pi) times (Earth’s radius + orbit altitude) *squared*
Thus, if the average orbital altitude is 1,000 miles the surface error of the orbital sphere is
(4) times (22/7) times (4,000 + 1,000) times (4,000 + 1,000) = 314 million sq. mi.
thereby yielding an average “junk density” of 314 million / 18,000 which is equal to:
one piece of junk for each 17,400 square miles. That means there is one piece of junk for each square measuring 132 miles per side.
Is that much of a problem?
A spaceship with a big sling-shot. Load the debri and aim towards the sun
Put your slide rules away. This is not a physics problem. This is an economics problem.
There is a cost associated with tracking, avoiding and not avoiding space junk. NASA and other space agencies track these costs. These costs are infinitesimal compared to the cost of any potential cleanup plan. None of the plans even make it off the drawing board before they are deemed to be not cost-feasible.
“First, build a rocket …”
“Stop right there …”
It might be fun, but it’s a waste of energy to try to figure out how to do this until this becomes a real problem. And it won’t become a real problem until the cost begins to approach the cost of a potential cleanup solution.
Ok, we’ve abused ole’ Bob pretty good there. Here’s a realistic stab at solving the problem:
Idea 1 – Maybe something like a kevlar based system is what you want, working on the principle of an aircraft carrier arresting system. You let the objects hit and punch through a kevlar barrier. Each hit would take some energy from the object, hopefully eventually forcing it into a lower, decaying orbit. The target would be stabilized by some sort of propulsion system (ion?) and once the useful life of the system had been exceeded it could be programmed to defurl and deorbit. Size of target – as big a could be practially controlled. Of course there are risks like damage to the control systems…
Idea 2 – Sow a defined area of space with some type of abrasive substance, I like moon dust. Objects entering this cloud of moon dust would experience a reduction in velocity and hopefully eventually be forced into a decaying orbit. This cloud of moon dust could be deployed in a decaying orbit itself so that most of it would eventually enter the atmosphere.
Idea 3 – A space garbage guy stationed at the International space station and equipped with an ion propelled, solar powered tug to go out and dispose of the larger objects when the opportunity arises, one by one. I’m sure there are some objects in orbit that could be disposed of this way.
Idea X – Any idea to whittle away at the problem, bit by bit.
Nets, pfft! My idea is to send up an apparatus with many, or massive tanks of compressed “stuff” that, when combined in earth orbit, will form a giant ball of taffy. Think of that “Great Stuff” expanding foam.
So, we should many of these satellites up into orbit, get them into right orbit and speed, send the signal and they explode into giant balls of space-goo that will blot up and collect orbiting debris, then orbitally degrade and burn up on re-entry.
Well, not goo or taffy, since it would harden into something like styrofoam.
The polar-orbit collector net is problematical (to put it mildly), for reasons already mentioned. But counter-orbiting “pea shots” may do the trick more directly, and at a fairly low cost, at least for junk in low Earth orbit (LEO).
The key here is to realize that for an object in LEO you don’t have to change its velocity very much to put it onto on orbit that will bring it into a thicker part of the atmosphere, or even on a collision course with the Earth’s surface, and so “dispose” of it quickly. A change in velocity on the order of 1%-2% is all that’s needed.
Imagine an object orbiting at an altitude on the order of 100 miles above the Earth’s surface — this is LEO by any standards — and assume that its orbit is perfectly circular. If we now reduce its velocity, suddenly, by 1% but keep its direction the same, then it will be in an elliptical orbit, with the point at which the slow-down occurred being its highest point above the Earth (apogee) and the opposite side being its lowest point (perigee). With a basic high-school physics (conservation of energy and angular momentum, or equivalently using Kepler’s laws) one can show that, for small changes, the percentage difference in orbital radius at perigee versus apogee is the same as the percentage change in velocity at apogee compared to the original velocity for a circular orbit.
Got that? It means that if we slow an object down by 1%, then its height above the center of the Earth on the other side of the orbit will be 1% lower than the height at the point it slowed down, ie the height of the original circular orbit. All low Earth orbits have an orbital radius basically the same as the Earth’s radius, about 4000 miles. A 1% decrease in velocity, then, will lower the altitude a perigee by 1% of this, or about 40 miles. Measured above the surface of the Earth, this means that the object’s altitude decreases from 100 miles at apogee to just 60 miles at perigee, which is starting to be enough to bring it into contact with the thicker part of the atmosphere, which will slow it down even further and its end will come quickly, within a countable number of orbits. Change the orbital velocity away from circular by 2%-3% and its perigee will be within the Earth, and so it won’t survive even one more orbit.
So here’s the strategy: launch into counter-rotating, somewhat-inclined but near-equatorial orbit a large number of 1-Kg “smart peas,” that have just enough rocket power to make a fine course correction. [I think they may still have some left over from the old Reagan-era Star Wars program.] As with Bob’s original argument, each one will have many, many chances to “cross paths” with each of the junk pieces in normal, near-equatorial orbits. Some of those will be sufficiently close encounters that even a little bit of rocket power can put the pea on a collision course, if you calculate well enough in advance. If a 1-Kg pea collides and becomes embedded into a 100-Kg object going the other way, the resultant combined object will be slowed down by about 2%, which should be enough to de-orbit the junk piece permanently. Even if the result is not a single, combined object but an explosive mess, then the _average_ velocity of the debris is still lower than the circular orbital velocity by 2%, independent of the details of the collision. Surviving pieces which are not sufficiently slowed-down can be re-targeted in later follow-ups as necessary.
So, with this approach we can de-orbit junk in LEO at the cost of launching about 1% of the junk’s mass into a counter-rotating orbit — somewhat more expensive than a typical orbit, but not prohibitive — and the “peas” can actually be fairly low-tech as long as we have very good orbital calculations. A penny-on-the-dollar solution enabled by lots of computer power — just the sort of approach Bob should love!
You are seriously suggesting that a 1kg shell hitting a 100kg object at 50,000 km/h will become ‘embedded’?
There was also a 26-episode 2003-2004 Japanese television 2003-2004 anime series called PLANETES where the heroes did some serious orbital garbage collecting. They only went after the big stuff. For my money it’s the best science fiction anime to come out of Japan in a very long time. It’s available in English dubbing on DVD with the original Japanese track as an option .
It’s based on a manga. I read the version translated into English, and I think I liked the books better than what was in the anime.
Why do the older comments have to appear via a link…especially located at the bottom of the page? I can page-down hundreds of pages, if need be, effortlessly. This “feature” is confusing to readers when some comments appear to be non sequiturs. And it doesn’t show the full impact of responses.
This article is one of the stupidest things I’ve read on the internet. I would laugh you to scorn if I knew you.
Really folks — Lighten up.
In a way Bob is messing with us. Enjoy it. Let yourself smile.
In Bob’s solution he did the calculations right and showed his nutty idea would take almost 40 years to work. He admitted it was impractical.
Okay, what do you want?
Bob offered a solution to the problem and by showing how long it would take to work, he showed us the magnitude of the problem. We’ve learned there is a problem with orbital junk and it won’t be easy or cheap to fix it.
Lets keep things in perspective.
Let’s put this into perspective:
First of all, we’re talking about miles above the earth, and 3 diminsions. That’s millions of miles to play with. We’re talking 18,000 piece of space junk. We could pile that amount of junk in someone’s back yard. The chances of that debris hitting anything important is slim to none! It’s like worrying about a semi in florida hitting the White House! I know, NASA gets riled up at the slightest hint of danger, but give me a freaking break!
Instead of worrying about cleaning the debris up, I think it woudl be more feasable and practical to worry about protecting the space around the space station, by putting up a “barrier” around it (maybe put some “nets” up). Something that will attract any debris around the station and “trap” it, until we can properly dispose of it. Maybe put the trapped debris into a shuttle of some kind and point it toward the sun!
Why burn it? What a waste. We wasted literally tons of fuel to put these hunks of metal into space, and something like aluminum or steel in a reasonably processed form is hard to come by in earth orbit. Plus, once you’ve got it all in one place, it is no longer a risk. Then you’ve got a worthwhile economic justification for this mission! People can pay you for the hunk of metal they need for their mission years later.
A number of people have theorized on the value of using spent rocket boosters as spacecraft skins/frames and/or station habitats. Its only a little bit of EVA welding to make one these things airtight. The tricky part is orbital capture. But you’ll have already done that.
Also, I imagine that if you actually worked out the algorithm you’d find its gonna take a lot more fuel than you think or its gonna take a very long time and the impacts are going to be high velocity.
[...] technology writer RobertX. Cringely posts about space trash, recognizing it as an additional barrier to spaceward movement. Why leave this manmade hurdle in [...]
Replace “garbage” with “another nation’s military satellites”. Congrats. You might have sparked the next arms race
Instead of a travelling scow you deflect or ignore small pieces and for larger pieces shoot tiny robots that project a superstrong filament to a nearby spacestation. Filaments are captured and the large pieces are reeled in slowly and the microrobots (fine nanomachines) are recycled for reuse.
To clarify the microbots would be shot onto the large pieces. Anchoring to these pieces and webbing the thing together so you reel it back in one piece are both fairly trivial.
The trouble is that aside from the debris of a recent launch all that junk is moving on wildly tangential vectors due to tidal forces. I don’t think a single Quark-class garbage scow could carry enough fuel to go after more than a few pieces at a time.
Don’t disparage lasers, btw. The new 100MW military lasers under development could vaporize anything under 1-2 kilos in mass. Judicious targetting from higher orbit could send some of the larger pieces careening into the atmosphere to burn up. Oh, and many of the “dead” satellites up there are actually just in standby mode and have enough reaction mass to crash themselves if the crowding becomes too great.
As for the “is that much of a problem” argument, one of the space shuttles came back with a 1″ gouge in a forward viewing port caused by a bolt off a Russian probe from the 1960s. A couple of satellites – very, very expensive satellites – have died suddenly and mysteriously, after having flown through probable debris clouds. Launches from each facility tend to orient along well-defined “skyways” to their intended orbits and while most of the stuff that falls off tends to burn up right away, some of it makes it into orbit and orbits being what they are tend to hurl the stuff back ’round at least a few times before friction knocks them down. It’s starting to become a serious trafffic management problem with the ever increasing # of launches.
A net won’t do : if the piece is too small, it will pass through, if it is to big or fast it will destroy the net. My silly idea : how about a largish sheet of polythene : on impact of the particle the kinetic energy should vaporize and form a burst like a braking thruster, reducing the velocity and therefore send it to a lower orbit where the drag of the lower atmosphere will take care of it eventually. The aim is to reduce the orbit lifetime from decades to hopefully months.
We should only clean for safe corridors in orbits we are interesting in, like with mine sweeping, no point in cleaning the whole of the ocean/space.
And of course the remnant of that PEsheet better shouldn’t fall on a plane below.
Garbage scow captain and galactic chef — your careers of yesterday’s tomorrow!
Big Blogs…
David Archie pics spam!! From the Grammy Foundation Cue the Music event that he tweeted about! thanks for the twitpic taylor_ rei! and thanks for these pics posted on IdolForums , they’ re from the photoshoot with Rick! Major drool warning!…