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Nanosatellite Takes Out The Trash
michael.creasy writes "The BBC has a article about a new nanosatellite due to be launched later this year. The idea is that the satellite be used to latch on to and slow down junk in space so that they will fall out of orbit and burn up on re-entry. " The only problem, as the article points out, is that there's no one really interested in purchasing this right now. Still, it's a pretty cool, especially if the price points are correct.
As it's a single-use thing, there's little need for it to store much fuel.
Mir? Though seriously, why is price a problem? If a joint international venture did something like this to clear dead satellites out of the useful orbits for use by new ones why not just bill the companies/agencies that put up the dead satellites in the first place? It seems like they're the ones that left their space junk floating around.. why shouldn't they be liable for the bill to clean it up?
You're on the right track - but an ion engine would mean propellant, which would indicate a set life-span for the equipment.
Since this device is intended to operate mainly in low earth orbit, why not use the earth's magnetic field, run a current through an extended tether, and bias the craft for a higher velocity? Solar cells provide the power. That would drastically improve it's longevity, and usefulness.
Frankly, $100,000 for suiciding to bring down a loose lug-nut seems pretty silly. With 68000 objects needing removal, that's $6,800,000,000 (plus the nontrivial launch expenses), I can think of a lot better things to spend the money on. that's a *lot* of money.
If it ain't broke, fix it 'til it is!
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Something tells me that "space junk" would be a great way to blockade a planet from interstellar trade. . .
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Just release a couple million 1" ball bearings into the planet's orbits. With the added annoyance that these things will be raining down on their heads for several years thereafter.
No, wait, an advanced alien race would use centimeters, not inches. .
If it ain't broke, fix it 'til it is!
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nah, I flake-off and loaf. Read slashdot, while I'm supposed to be working for my taxes. When I'm working for money for ME, that's when the real productivity starts. Yessir! minesweeper!
If it ain't broke, fix it 'til it is!
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Maybe DuPont and Dow should clean up the atmosphere of CFC's. Maybe BPAmoco, Exxon, etc. should clean up the atmosphere of the excess CO2, and other crap, especially since it was proven that they basically forced the destruction of any public transportation infrastructure in America to promote the automobile. Maybe Monsanto should be liable to go through every individual plant organism in the entire world, and restore their genetic codes to what nature evolved, rather than what they picked up from GM crop pollen that blew their way. Maybe Microsoft should be responsible to go to every computer and remove all MFC and Visual Basic code polluting the info-environment. TV Broadcasters should probably be held responsible for travelling at faster than light speed to head off radio-waves from TV signals, and intercept them to prevent them from reaching an alien civilization which is liable to notice that we'd make an excellent slave-race.
Let's make these motherf*ckers PAY the real costs of doing business - not let them pass it on to customers while they profit.
If it ain't broke, fix it 'til it is!
These are my friends, See how they glisten. See this one shine, how he smiles in the light.
I shouldn't have, because:
50 buzillion other people had already posted it further down the thread - I hadn't read that far yet.
If it ain't broke, fix it 'til it is!
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You're right, and actually, as I was writing the comment, I was thinking of mentioning that method of staying in orbit.
I didn't because:
A) I hadn't heard of anyone using it, so thought perhaps it was difficult to get adequate speeds.
B) I figured I'd better pick the hot propulsion tech of the day if I wanted the question to make sense.
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Let's hope they don't just all start latching on to each other ...
Gee.. sounds alot like how the FCC allocates bandwidth - good luck finding a slab of frequency for less than a million bucks! I personally would like to have the ability to launch my own satellite without having to be a multi-million dollar corporation.
For all the naysayers above me who claim (among other things) that moving at the same speed in orbit is the same as moving at the same velocity, the dudes at Spacecamp told me that the shuttle usually comes back with several sizeable dents from orthogonal collisions with microscopic paint chips at relative speeds of 10,000 mph. The windshield is half a foot thick and made out of really expensive reinforced glass/plastic/metal/what-have-you, and there's still a significant risk of it getting smashed by a chunk of metal.
Humans' ability to fsck up environments seems to have increased geometrically. In less than 20 years of commercial space exploitation, we've managed to screw up a volume, not just an area of the world, to the point where things as ridiculous as £100,000 orbital garbage collectors have started to seem like `not such a bad idea'.
Sigh. My children are going to be angry at me.
The problem with this satellite is that it needs to go out, chase junk, match velocities, and then latch on and bring it down. With such a small satellite, I can't imagine it being able to carry much propellant.
How many satellites are you going to need to bring down all those thousands of paint flecks and loose bolts? How many more bits do you think would be released if just one nanosatellite screwed up and got beaned by an orbiting wing nut?
There are a bunch of other ideas out there that (at least on the surface) sound like they could be much more economical. For instance, a satllite that was just a giant block of aerogel. It would weight at most just a few pounds, and it would do nothing more than just sit out there for a few years, letting all those little particles embed themselves in the block until it was ready to be de-orbited.
Funny that. As a sophomore in college (94-95?) I had a paper published on how graph analysis can be used for robot motion planning. As my example, I used OSCAR (Orbital Scrap Capture And Recovery) - a satellite equipped with a few robotic appendages for catching, disassembling and recycling space debris.
Anyway, my thinking was that letting all those refined metals burn up on re-entry was a huge waste. If instead, a booster or another large piece of scrap could be processed in orbit (focused solar light cutting torch or the electricity producing tether mentioned in another post) then these materials could be used to help construct the ISS. After all, at the huge per pound cost of lifting materials into orbit, and with so much of it already up there...
Now, certainly, the living components, computers, and things of this sort still need to be hoisted up, but much of the shielding materials and even some structural pieces could just be scavanged as they pass by. How many dead satellites up there still have usable solar panels, spare propellant, servicable tranceivers to use as backups or to be retrofitted onto probes... Shame to just let it all burn.
Most of the crap that's flying around up there is useless pain chips and items the size of a dime, but the big pieces ought to be slavaged (if a cost effective way can be developed) since they are made of 'space age' materials, and so expensive to manufacture.
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What would have me worried is the cameras on these things. I'd be worried that it might recognize something useful for garbage and "escort" it back to earth...
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Yes, you are right. We need more taxes!
I only worked through May this year just to pay taxes, that wasn't enough. I want to work 'till June next year. In fact, if they don't add more taxes next year I'll just send them the extra money anyway. Just because the government is so damned efficient at how they spend my money and fund such streamlined programs.
Actually, now that I think about it I'll just work and pay all my money directly to the government and live in a government-funded shelter. I'll go to the library for Internet access... it's not as good as my DSL but at least it's funded by the government and everyone is sharing the bandwidth instead of me just hogging my own DSL.
Thanks for starting the ball rolling on this great idea!
Just a clue: if you currently reside in a country that embraces capitalism, I suggest you leave as soon as possible and see what life is like elsewhere (I would bet you have never experienced this - otherwise I'm sure your tune would be different). I guarantee you'll be back.
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And good ol' capitalism supplies the answer.. someone comes up with a way to "clean up" the mess. Face it, if the problem ever gets big enough, companies will trip over themselves to buy these things to clean up the areas around their satellites / spacecraft, as the cost is peanuts compared to catastrophic vehicle loss.
Acutally, if we would just privatize orbits around the earth this problem would go away as well. Externalities tend to occur when you have common goods (like orbits) that go unowned, so no one has a vested intersted in keeping them clear of debris. Sell of orbit slots, or something similar, and the market will take care of everything (and you don't have to waste my tax dollars on it, which is a plus. And it will piss of the liberals, another plus.)
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My understanding of this is that they'll only clog up the heavens for a short time, as once a satellite stops correcting its orbit it'll eventually burn up by itself.
A challenge for evil geniuses: what's the cheapest way to bring down the most satellites in one pop, assuming you're just going to use the threat for extortion, and don't care if you make satellite-space unusable forever?
You'd probably want something that spews spacedust in all directions over a range of altitudes...?
Well, that was also my first thought but I wanted to avoid the effects of random ionizing radiation passing through a capacitor with such a huge capacity. I figured it would be easier to design around gyroscopic effects than deal with safely venting plasma blasts.
Good point. Shall we chip in on a $1,000,000 satellite with a tether on it and fly it out to an asteroid? We could try an electromagnetic tether against the heliomagnetosphere and bring the asteroid over here where it's useful...eventually.
Use the tether's electricity to spin up flywheels, and have the junk grasper not be a single-use device. When the junk is sufficiently decelerated, release the grasp and use the flywheel to energize the tether to accelerate the junk hunter back up to a higher orbit. Use gyroscopes to alter attitude for maneuvering to go catch another piece of junk.
We don't need a junkyard, as the manufacturing effort needed to recycle obsolete materials which have been damaged by space is too much. It's undoubtedly easier to get fresh materials from the Moon and toss it up from there -- except for some of the denser elements, but we could launch the needed components from here and let them be assembled up there where space is cheap and G-forces are the least of the problems.
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I see... You're suggesting the first remote-controlled pogo stick...
Don't scare me like that, /.
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Oh shit! I just game AOL an idea: AOL-MOON! Just think how shiny a moon of Cd's would be!
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that's a good idea! Use the existing junk in space to bring down the rest of the junk rather propelling more junk into space that will probably be a dud and end up floating around in space (more junk).
You gotta love the liberal use of buzzwords. Is anyone else bothered by the use of the prefix "nano" to describe something large enough to have a 6 kg mass? After reading the headline I was expecting something the size of a pebble. I guess maybe they'd call that a "picosatellite"...
:-P
Maybe this is proof that the British really don't get the metric system.
Only if two objects are going in the exact same orbit and the same direction are they safe. If you want to hit the first object hard, you put the second object into the reverse path on the same orbit, or some other crossing orbit.
For shuttle altitude orbits, you get about 30,000 mph of delta-v when the collision happens.
This still has a problem of a bullet hitting a bullet, but that's why they use guided missiles, not bullets.
This is a no-brainer, folks. Use robotic solar or laser furnaces to recycle all the space debris into girders and other parts for the International Space Station. Separate plastics and metals, should be realatively easy. Each Kg taken into orbit is VERY expensive. Reuse is key. Goal: never allow an orbiting atom to return to earth's surface; use it to go where no human has gone before.
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Screw space, when are they going to break out the gutterbot to clean up all the crap in the neighborhood, keep rat population down, make sure every car on the street has the proper air pressure, and return stray pets.
Maybe I'm crazy but cleaning up space is alot like keeping an impeccible front lawn and living in 3 feet of trash.
To do that you need a station already in place - which costs quite a bit - it would only be worth it if you had a very large ammount of metal to work with.
The ammount you could possibly place in orbit just doesn't justify the cost of a factory to deal with it.
Unless you got metal from asteriods - but in which case you'd still not need the metal in orbit of earth - you'd be able to easily get it from asteriods and there's lots more there.
Sort of a chicken and egg thing, but in short metal in earth orbit is just never going to valuable, since by the time it is useful there'll be better places to get metal. Until then we'll keep having to get it from the planet.
-Ariel
Um, comparing the ammount of metal on the planet vs the ammount of metal in asteroids, vs the ammount of metal you could possibly place in orbit - I don't think anyone will be harvesting the junkyard.
-Ariel
The bit I liked about this is that the satellite is so cheap - a million for a full launch. But surely the can do something more interesting than this.
I guess an orbital collision could be devastating (but incredibly unlikely), but are they going to make one of these for each of the thousands of pieces of junk up there? Besides, the junk may be useful to someone if there's ever a space colony - it saves the effort of carting stuff up to orbit.
Why can't they put together cheap science projects or communications satellites instead? I'm sure there are tons of projects which could be done with a 6kg satellite which would be far more productive.
And we all thought that Quark was fiction!
Another problem would be the accuracy of these satellites. If they miss the debris they're targeted to latch onto, that's more revenue lost.
Even if the debris can be approached, a slight miscalculation in telemetry could bump the target away from the recovery craft, where it could remain in orbit with an even less likely chance of plummeting into our atmosphere.
why bother with a flywheel? Everything could be solid state. Charge up a huge capacitor instead.
Yeah, but how do satelites and space shuttles get into their orbits? They have to be launched. At high speed. And pass through orbiting space debris.
1 million is pretty steep for a garbage collector... how about using high powered lasers to blast the sky clean?
Just a thought...
If the price point is really correct, then I can think of one piece of junk that i'd like to see fall out of orbit... did anyone say "star wars"?
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Does that, buy any chance mean, "Talk about the pot and the freakin' kettle"?
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This has nothing to do with Capitalism. The Soviets have launched far more satelites than anyone else in history. The US is a very distant 2nd. This is an issue of responsibility. All nations that are responsible for space junk should help chip in on the cost for removal. Just think, we could attach a permanent space bound garbage truck to the international space station. It would fill up and then unload over the pacific at a predetermined time and location.
Some drug lord/evil dictator could launch a barrage of garbage collecting thingies to pull down...say...all the GPS satellites!
Or DirectTV could take out all their competition.
Who has jurisdiction over crimes committed in space?
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A Scott Bayowolf cluster? That would be keen.
That is correct, but then you wasted a few million dollars on a fancy show for amateur astronomers. In addition, whilst the sattelite remains in operational limbo, it is a target for space debris. And if it is hit, then more debris is created. Also, if the sattelite is constructed imporperly, or properly depending on your view, it could cause damage when it deorbits. There have been 3 incidents now where space debris in the form of red hot shrapnel, has scattered across a town filled with people. We got lucky when Skylab landed in the outback. It could have been a lot worse.
Pax Digitalia
Attach an inflatable aeroshell to expensive sattelites that have been abandoned, and deorbit them. We need to start salvaging defunct craft, instead of letting them clog up the heavens.
Pax Digitalia
Repairing or upgrading old satellites is like suggesting to someone that they should upgrade a 486 computer. Anything over 5 years old is essentially obsolete. It'd be a lot cheaper just to put up a new satellite.
I/O Error G-17: Aborting Installation
Uhm, no.
Things deteriorate. Satellites that have run out of power eventually fall apart. They're not so much concerned with satellites knocking into each other as *fragments* of satellites hitting, say, the space shuttle and turning the Elbonian envoy to space into Swiss cheese (how's that for a diplomatic incident).
Have you ever seen the damage that space shuttle orbiters have come back sporting after a jaunt around the earth? Specks of dust nearly shattering viewports are not uncommon. Moving at whatever velocity they do (I won't bother pulling a number out of my ass here, but it's an obscene speed), even paint chips can do untold damage.
So space is a dangerous place, and we're not helping. IMO, we need to set up a Celestial Shop-Vac before things like, oh, say, the entire Iridium network, decide to flake out and create more of a hazard for spacefarers.
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That depends on your unit. In addition, you can build your own GPS receivers that bypass those. You can get download the specs from the net from the NRO site.
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Gyroscopes are needed for attitude/pointing control, and has no relevant to chips i.e. you can't replace a gyro with a chip (a laser gyro is still a gyro).
:)
Russians build things big out of historical/cultural reasons : their engineering is very robust and they do not often "go for the last mile" like western engineers do.
Russian efficient boosters are a Myth, their boosters are less efficient than most western boosters. The numbers they are throwing about are "fudged" in the sense that they add "back pressure thrust" to the numbers, while the standard western way of calculating efficiencies do not do that.
The cheapness of their launches is due to
(a) their rockets are cheap because their labour/material/tax/overhead are cheap
(b) they need to be cheap to compete with the protected western markets (eg. NASA forces NASA funded projects to go on American launchers.)
(c) they have lots of "cheap ex-ICBMS" converted to LV and are selling them, all due to the START treaty (in fact they have a LV call "START-1", a converted SS-21)
Any questions?
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In a nutshell, yes and yes.
Yeap. GPS works as long as you can get a fix to the signal. If you are higher, and get Line of
Sight to more sats, you can get a better fix. So it actually works better in space....
Last time, before the recent overturn of the "selective availability" by Clinton, you cannot get velocity info above a certain velocity (eg. so people can't use GPS to control a ballistic missile headed for D.C.). But now SA is dead, you can get velocity info in space too, which is great. Problem is that you have to buy/build GPS receivers capable of doing that.
There are a ton of sats up there using GPS as navigation tools.
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Deorbit junk? Come on Craig....
Snap-1 (actually an acronym for Surrey Nanosat Application Program) is probably
not good for this de-orbit thing that they are talking about : it's all about the amount of deltaV/mass (change in velocity per mass) your thrusters can provide and this number is constrained by the amount of fuel and the efficiency of your thrusters in converting this fuel to thrust. (about 20% for the cold gas N2 thrusters snap probably has). So how they deorbit a Arianne IV spent booster with 0.5, which is unlikely given the stuff they are putting on board...
(Caveat : the size of thrusters is not a problem : one can always fire for a long time as long as fuel is available.)
But way to go SSTL!
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Not really, when you count the huge launch and development costs. And quite often there is nothing wrong with an old sat other than it has run out of fuel. A few months back there was some news about NASA (I think) developing a robot to carry out refueling as a cheap way of extending satelite lifetimes.
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One of these days we;re going to have a moon base, why not fling all the dead space trash at the moon, as, say, spare parts should any of the moon base's stuff break? a tad bit of foresight might be good.
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The way we dispose of space trash has always, on some level, irked me. I mean, here's this multi-million dollar lump of metal, and we send it to a fiery death in our atmosphere, where it just vaporizes, making the air a little less clean and ensuring that our supply of useful metals is just a little lower.
Now here's an idea for a nano-satellite design: the recycler. In ten years, you could simply purchase a few of these for cheap, and they would seek out space garbage and reuse whatever's still working (solar panels, some computers, com equipment, etc.) while melting down the rest. Once all the right parts are collected, you nano fleet builds a brand spanking new satellite right in orbit. The cost of launching these little machines is orders of magnitude less than sending completed sattelites into space, and you pay nothing for materials.
Of course, eventually we'll run out of space trash. At this point, we could begin towing asteroids into high orbit. Maybe a tax on orbital development could fund the towing.
Just an idea...
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Because a large satellite might be detectable, how bout a series of tiny sticky satellites that just add mass to an enemy satellite. Of course, my physics training (very little) doesn't tell me how many sticky's it would take to alter the orbit.
Shoot, if you really want to take a tangent, why not modify the technology from a satellite to a weapon police departments could use to stop speeding motorists.
Ok, Ok, I'm really getting off-topic now. But the idea is pretty interesting I think.
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There are a lot of materials available and as the article states some of them have been tested to last upto 3 years in orbit and others with decades of lifetime are on the design board The shot about carbon nanotubes basically shows your ignorance aboutthe issue and a desperate attempt to sound informed. There is no need for strength in a low g tether and that is what carbon nanotubes are usefull for And no they dont need to tether to the ground . the tethers are free hanging and if u had not cut your physics classes u wld know that the ionosphere can provide a good enough return path. And it reflects very badly on the moderators that what was obviously a troll got moderated upto interesting!
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he's right. the real interest in this device wouldn't be in simply disposing of extraterrestrial garbage, it would be in destroying the enemies satellites. nations rely so heavily on satellites these days that if you could destroy all of a nations satellites ASAP the war would be over before it started. i can almost see future military strategy classes teaching satellite manuevering to destroy the enemies anti-satellite satellites before they get yours.
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Because, unlike Americans, Russian technology assumes that mechanical parts (as geroscopes) are more stable and have less chance to fail, unlike "selicon bullshit", made in USA.
Gyros are rubin based (for precision), work like clockworks. Chips can be taken out of order by a simple radiation stream, directed at the sattelite orbit. Or a simple magnetic discharge would cause enough trouble on the orbit. Now try to take out a mechanical tank...
But, due to mechanical components, the size is increased. But this does not matter, Russians have the cheapest kg/$$$ rate to put things on the orbit anyway (their boosters are THE most efficient ones in the world).
Well, it's all well and good when space trash in the same orbit as you goes at the same speed as you, but when it's going in the opposite direction...
Hey, it could ruin your moon vacation!
Donny
Heck, that's EASY. For that matter, you could do all that for under $50k - just launch an 0.6kg bag of sand retrograde into the geosynch band, with a tiny cherrybomb in the middle of it, and you should be able to take out just about every geosynch satellite in orbit, PLUS keep anyone from launching any more for a few good years. Now THAT'S some extortion money.
-Hentai [in vita non pacem est]
Nanosatellites are all good and everything, but I think that we have better things to spend our money on. Nanosatellites sound fine, but, talking about nanotechnology, when am I going to get free food and perfect genes? Nanosatellites seem so, well, small now.......
Companies nowadays are responsible for cleaning up messes made years ago, whether or not they originally new the mess would be hazardous to the environment. For instance, in one case in upstate Mass. involving GE, the company was forced to dig up dozens of plots of land they had created for employees using dirt that was used to soak up chemicals from industrial plants. At the time, the chemicals were thought to actually make the soil more fertile, but 30 years later they found out it was carcinogous. This law makes GE pay for the damage even though it didn't know it was inflicting any originally.
If space can be seen as part of the natural environment and public domain, then I don't see why companies can't be held to the same law up there. In this case, however, they have no excuse as we have known for decades that space debris would be a problem eventually.
This is very cool, but since it's fully automated, what can be done about a power source? It's obviously not solar-powered, and the gas supply would run out pretty quickly, I gather.
Other than that, I'm sure this is a cool project. It's too bad no one's interested, because there is so much space junk out there. Relatively soon people will have to be interested, when it becomes dangerous taking anything up there!
Are we seeing the beginning of a new trend? In the wake of "electronic" , "digital" , "cyber", "web" etc, all cool tag-words/adjectives added to make a product seem more modern and "happening" but often having little to do with the tag, will "nano" become the buzz-word of the first decade of the new millenium.
These satellites aren't nano, they don't involve atomic or molecular level manipulation and they are not build in a nano scale.
Why aren't they called "micro-satellites". A much more apt word.
I haven't heard a lot about junk in space, but this really explains the idea that time (idea of) tears time (use of). If only junk did not exist in space, maybe technology would have advanced further by now. Little steps sure do lead to a lot; however, big steps kill awareness and time. This is ONLY my opinion, but I hate time and have since I reached the age of acknowledgement and self-thinking. Although I am not too fond of time, I wear a watch because others ask for the time.. I have a phone because others call me.. but I have a computer because my brain likes to think.. It is good that someone is being traditional and supplying for the needs of the place beyond our world. If only we were not trapped in time..junk would not exist.
Personally, I feel that we should contract the man in the moon to swoop down and eat all of this so-called "space garbage."
"They were designed to decelerate junk while eating some of it for fuel and reproduction... Now get these #$@! things off my space station!!!!!"
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Possibly a more interesting design would use the junk itself for propulsion. It would only work against reasonably small stuff, but if it can grab it and throw it into an unstable orbit, well, the satellite gets a push in the opposite direction.
If it can see many pieces of space junk, then it can actually throw one piece and use the push to put it into position to grab another piece. It'd need a backup thruster, in case something goes wrong, but if something like this was, say, solar powered and took its time between throws, it could be in space for quite a while.
In a desparate attempt to save open source news, a team of international astronauts launches a million snap nanosatellites which then latch onto the rock and steer it off course.
But then, the last unit has malfunctioned and one of the astronaunts, Tyler's boyfriend, who is not played by Ben Aflack, space walks and pushes the asteroid out of harms way.
Whew!
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Very few satellites are as low as 150 nmi and LEO environments can be up to 1000 nmi...so you are talking about a larger section of space.
Also, that 65,000 pieces of space junk is not just limited to LEOs, but goes all the way up to GEO which is ~22,000 nmi...much more space than you are suggesting.
furthermore, typical orbiting times for a revolution of a LEO are approximately 1 to 2 hours.
The junk is well monitored and while I am not happy it is up there, it is not much of a concern in all reality to orbiting satellites and the space station.
IIRC, a satellite in a geosynch orbit is motionless with respect to earth, but one in a much lower orbit has to travel much faster to maintain orbital velocity. The shuttle and all garbage in its orbital height has to maintain a high speed (I think it orbits something like every 90 minutes in at least one common orbit height), along with everything else (and sometimes in opposite directions!!! So although there may be more sats in geo-synch orbits, the really fast moving garbage is in LEO/MEO, and this includes old rocket boosters, lost tools, disposable shrouding from rockets, etc. Stupid, huh?
I do recall seeing a picture of a couple inch thick observation window on one of the shuttles that got hit by a fleck of metal, it blasted a crater into the (plexi?) glass, about 10 inches wide, and it looked a couple of inches deep....and this was just a fleck of metal, let alone an actual object. Would really suck to lose a shuttle to a 1/4" lag bolt.
Grab one of the earth passing asteroids, put it in orbit, and it will sweep the junk all by itself. Plus, the junk is not entirely destroyed. It cost money to launch that mass, leave it up there.
Damn snooty, highbrow Brits... Think that just because they know how to use the metric system correctly that they are better than NASA... hehehe...
I mean, I agree that my figure is probably off. I'm no rocket scientist, and I had to dig hard for the figures I did come up with, however, most of the launches are to LEO, hense that's where most of the debris is. Not many satellites make it to GEO (communications sats, monitoring sats, etc). Not even the GPS system is in GEO orbit, at least, I don't believe it is (Oh for an easy resource for all this data :P). 65,000 objects are trackable objects, I wager. Untrackable objects are things smaller than radar can pick up, and often, are the more dangerous of the two.
There may be 'only' 65,000 pieces of space junk, but keep in mind, these circle the earth at about what.. 15 minutes? 30? Certainly no more than 1 hour to circle the globe. The velocity of these things moving makes it even 'smaller', because collisions can happen all the more often with faster objects.
Depending upon the altitudes of the pieces of debris, their speed, size, and such, while currently it is possible to calculate orbits to avoid things in space, if you continue to drop things in orbit, junk pieces of disposable rockets, dead satellites, etc, it may get more and more difficult to have a mission where no 'dodging' of space garbage occurs.
I say.. we put it there, we clean it up. Simple as that. With the prospect of the Space Station in place, where dodging debris isn't as much of an option, how long will it take before something comes hurtling along and ruptures a portion of the station?
The way I see it, why not start the first scrap metal yard on the moon?
There's definatly a niche market for all that floating debris/hardware somewhere. Even if it is only in some sci-fi movie with big breasted aliens.
I worry about a bird getting sucked into the engine of the airplane I am flying on. Maybe they could develop some similar removal system for birds? Eagles may soar high, but weasels dont get sucked into jet engines.
I don't think anyone would argue that taking out the space trash is a worthwhile endeavor. But who would pay for it? Even at $10 mil for the launch, this is an expensive operation.
The BBC article quotes the developers as saying funding may come from the insurance agencies.
But I find this difficult to believe as the probability of collision (even for 65,000 pieces of junk) is still fairly remote (space is vast) and insurance agencies can most likely better secure themselves by charging larger premiums and "deductibles." Anyways, for many of these large space operations, the insurer of last resort are the federal governments. This is, IRC, the case for the Space Shuttle flights.
I think a better alternative is for major launch groups (federal governments and large private firms) to band together and institute some kind of a clean-up fee with each launch ... similar to the tax applied to beverages in aluminum cans instituted in many states, countries (in California, the cash-value deposit). Then use those funds to launch these Snaps (or their competitors).
I am, for the most part, a supporter and student of the free market ... but there is such a thing as market failure. And I think Space Trash is just such a case (usually occurs when property rights are not well defined ... as in the case of space)
What about different directions
I doubt it, the huge spy satellite would have far more fuel than a 33cm Snap, and could easily defeat one of them in a tug of war. But why waste your time to slow down and then destroy spy satellites like that when you could simply add a small explosive charge which would be more effective as a weapon (though admittedly not as a garbage cleaner).
GPS should work anywhere you can recieve the signal.
GPS defines a location as:
X Distance from Sat1
Y Distance from Sat2
Z Distance from Sat3
and so on
Which defines a point in 3D space that the reciever converts to Latitude, Longitude, and Altitude. It can just as easily define a point in space as on earth. The entertainment industry uses a similar system to allow moving lights to follow the performer. Several ultrasonic emmitters are set up in the corners of the stage and by listening to the time shift in the performer's microphone the computers plots the performer's position exactly and sends it to the lights.
âoeWho knew something as harmless as willful ignorance could end up having real consequences?â
How about just launching the nukes at the trash, and taking care of two problems in one smack? Moihoihoi
Can anyone explain this? It briefly mentions that the satellite contains "minature GPS navigation technologies", among other things.
How does GPS work when you're *in* space? Do you just get a readout of "37 degrees north latitude, 68 degrees east longitude, altitude 5,000,000 feet?" Can you see more of the GPS satellites at once and thus get an even beter fix on position?
I've never considered this possibility before.
hmm, mebe instead of using lasers ala starwars we could just have little intelligent bomb diffusers flying about disabling any warhead which happens to fly around up there..course nuclear subs/cruise missles are the bigger problem now
I wonder what a million AOL CDs burning up in the atmosphere would look like.
I hate to shoot a hole in your collision argument, but satalite collision is not a factor. Lets face it their may be a lot (65,000 by your account) of debris, but there is a whole lot more space. Also, if you would remember basic physics, all objects at the same altitude share the same velocity, so they wouldn't rip a hole in the side of the space shuttle because both objects would be going the same speed. Jake "Think before you speek" -Mom
>and what, precisely, are you going to make the tether out of? thus far (AFAIK) there is no
>material that is feasible. carbon nanotubules aren't long enough to make one yet...
>are you planning to tether it to the ground (since this seems to be what you're implying)?
No, no, this isn't a tether. It's a piece of conductive cable of a pretty good length, but nowhere nearly long enough to reach the ground.
This is high-school physics stuff -- moving a conductor through a magnetic field induces current on that conductor; passing current through a conductor conversely generates magnetic field.
By manipulating the amount of current you're letting be generated versus the amount of field you're generating, you can push yourself around relative to the larger field of the earth, speeding up and slowing down, and therefore achieving different orbital velocities.
Basically, you're using a long piece of strong wire as a magnetic "sail."
>and from where comes this "power" that you're running through the cable, if not from propellents?
>why would a "nighttime" pass need more energy storage than anything else? this isn't dependent on solar anything.
You've just answered your own question. During the day, the satellite would likely recharge electrical batteries with solar energy as well as with the current induced from pushing through the magnetic field, so nighttime manuevers would have more of a drain on the storage since there was only the one medium of recharging, and it wouldn't be used when you were creating a field to slow down. You'd want to do less moving about at night, for sure.
--
I don't see this as a general-purpose "lets clean up all of space" device, but I can see it being usefut for sweeping particular orbits, say, clearing out anything that's likely to come close to the ISS.
If anyone has a better idea, of course, I'd like to hear it! :)
and what, precisely, are you going to make the tether out of? thus far (AFAIK) there is no material that is feasible. carbon nanotubules aren't long enough to make one yet...
and from where comes this "power" that you're running through the cable, if not from propellents?
are you planning to tether it to the ground (since this seems to be what you're implying)? if you are, you can only have it in one orbit - geosynchronous - which would make it awfully hard to "go after" anything. and how big of a chunk of sky would this take up from aviation (safety margains included)? if not, how do you "run power" through the cable?
why would a "nighttime" pass need more energy storage than anything else? this isn't dependent on solar anything.
this is only the beginning of the problems (or ambiguities) with the scheme you've discussed... of course, if I've misinterpreted, please clarify.
Lea
There have been simulations that suggest that we may be getting to the point where we risk a chain-reaction that could make things very hazardous up there. One satellite getting majorly fragmented would result in even more -- and less easily-tracked -- dangerous-bits-o-stuff, which might trash a couple of other satellites, each of which might trash a couple more, etc.
To counter a couple of other misunderstandings I've seen:
(1) Yup, space is big. But the subset of space that's useful for satellites is less big.
(2) Satellites aren't all tidily lined up one after the other in perfectly circular orbits. Satellites can be in similar orbits and still have closing velocities that can cause damage. And satellites in different orbits can still cross paths, and the closing velocities there can be really nasty.
When you realize that if one of these hits a satelite or (worse) space, shuttle...at the velocity it's going...it would basically tear a hole right through it.
Um. I hate to point this out (well, no I don't), but the whole idea of a satelite hitting another satelite as massive speeds is kinda silly. You see, a satelite's orbit distance is regulated by its speed. If a satelite is going much faster than the other satelites, it will have a much higher orbit. The most common orbit, of course, it geo-syncronous orbit, or the orbit height that keeps the satelite over the same point on Earth at all times. Ever notice that the space shuttles don't do that? At the orbit they're at (most of the time) there really isn't that much junk. That's probably why they use it.
...worth it to get unlimited funding for NASA!
Here's how:
Like the garbace they're cleaning up, these nanothingies make really small holes if the shuttle were to hit them. But what if we could make even smaller robots (picothingies) to clean up the unused nanothingies? Of course that will create a similar cleanup problem and harder-to-find leaks when they hit the shuttle. But wait...even smaller robots could get rid of these robots!
I wonder how long NASA could keep this going...
--
Win98 sux without these 1337 toolz !!
Is it just me or does this seem like a relativly cheap way to deorbit critical military and communications satellites that are owned by unfreindly nations? I know that the US and the Soviets had both space based and air launched anti-satellite weapons, but IIRC they were very expensive and somewhat difficult to use (well at least ASROC the US air launched anti-sat missile required pretty precise ground/air coordination to get it right) These Snap satellites on the other hand are very cheap and in theory will work quite autonomosly of ground based control. It would be trivial to put a hand full of these in orbit near key military/comm sats of potential enemies and leave them dormat until the shooting starts, then right before you attack activate these "trash collectors" to deorbit the bad guys birds and well you get the idea.
On the other hand, &100,000 plus lauch fees seems like alot of money to deorbit one piece of space trash. If they can find some way for each one to deorbit more than one peice of junk in it's lifetime I could see this being a good solution to a growing problem, but a &100,000 suicide garbage collection mission seems a bit excessive to me.
"Listen: We are here on Earth to fart around. Don't let anybody tell you any different!" - Kurt Vonnegut
I think that there is way too much technology for us to use single use garbagemen.
How about one that "rests" in an orbit that keeps it in the sun (this is possible, no?) then "attacks" junk. Then deorbits it by pushing geting above and in front of the junk in a decaying orbit,then pushing off, stealing energy from the junk? This would improve its orbit, and degrade that of the junk.
I understand that this would be painfully slow, but if there were several of this things working (semi-)autonomously it would be workable.
-Peter
Slashdot cries out for open standards, then breaks them.
It's not fast enough to take out nukes, but it's an interesting play for taking out spy satellites. Since it wasn't developed by the military, it doesn't cost much, which means that multiple countries and occasional private citizens may have an interest in buying them.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
I agree totally. Plus, you can store a lot more energy in a flywheel of comparable size to a zapacitor, and the lifetime under this type of strain appears to be much longer.
I think this device and the needed control infrastructure could be built for less than $100 million and launched for about the same.
Absolutely. With tethers, speed isn't the name of the game, at least not yet.
Either way, the only energy that needs to be expended is in getting to the object. A good sized tether ought to be able to move the OMV itself around with impunity. Once you attach to the object, size isn't an issue, you just start expending power and let the conductive tether gobble up electricity in exchange for kinetic energy. Use a portion of the power to spin up some flywheels to fierce RPMs, then use that concentrated power to boost your OMV out of the death orbit it put the junk into. Find another satellite, rinse, and repeat.
Something cool about tether technology is that junking the stuff isn't the only option. Create a legal 'Junkyard' area in space that's at high altitude. Instead of de-orbiting satellites/discarded shrouds/interstages/etc, boost them all up to a parking orbit of sorts in the legislated 'Junk Yard'. There are orbits just one or two hundred miles higher that have lifetimes measured in decades because of lowered atmospheric density.
The junk yard concept is for the optimist that imagines a future where humanity will gratefully harvest the junkyard for raw materials in the future. The de-orbit option is for those seeking the easiest and relatively hassle-free option of fire and forget.
Are you absolutely without clue to the nature of energy management? Each pound of metal hauled into orbit costs between $5,000 and $20,000 each. The reason to use an orbital junkyard is to have access to metal without needing to pay to bring it all up.
A $.01 cup of water in Oregon is worth a lot more in the middle of the Sahara, pal.
Asteroids and the moon are the next step, of course, but you need to get to them before you can exploit them.
...unless you're suggesting all the commercial astro/cosmonauts just ride out to the asteroids on smelters with nothing but their spacesuits on. This isn't a ride to the local Dairy Queen where you can hang off the side of a truck.
Tethers have limited utility for roping asteroids. Unless you haven't noticed, there aren't any asteroids orbiting in low earth orbit, the place where electromagnetic tethers are effective.
The idea is to store the payload shrouds and dead satellites in a place where LEO industry can use them later. Perhaps the use they'll pick will be constructing devices to mine asteroids, but they need to get there first.
> OMV is not tether-based, btw. (I work with the guys that designed it, and they are always
> pulling out the little models and such. *Grin*) In any case, all you need is surface area, so if
> you wanted to do something fancy, consider just hooking on a big inflatable sail dohicky - cheap, low mass, and effective.
>
>If you have the power to spare for a tether, I'd wonder if it wouldn't be simpler to just use
>electric propulsion; for a few hundred watts and a few tens of kilograms (and a year or two) you
>can deorbit most anything.
The rest of your post was insightful, but these are critical errors you've just made.
A OMV stands for a 'Orbital Maneuvering Vehicle'. It is not a reference to TRWs OMV design for the Shuttle C program, or any other specific vehicle. It is a description of a vehicle that maneuvers things in orbit. That's all.
Second, the entire purpose of this design is to avoid using propellent entirely. A tether based system can stay up as long as needed and keep working for years, de-orbiting hundreds of satellites and shrouds before wearing out. If you used an ion drive, you would quickly expend your propellent after de-orbiting maybe one or two payloads. It's foolish, and hardly economical. That's the wonder of tethers: As long as you have power, you have movement.
Tethers are potentially the most important development in space travel since the fuel cell. No joke. No other propulsion system exists that can provide the thrust in LEO of a tether, nor does and device lend itself anywhere near as good to ease of deployment. A solar sail is a fanciful idea for this purpose and would be quickly destroyed by debris before it put out enough thrust to move a single kilogram out of orbit, and it would be unbelievably difficult to build and deploy for this purpose.
This article is a bunch of BS. I work in the field they speak of, and there is *no freakin way* that they would be able to deorbit any significant amount of debris with this method.
There is so much debris there, all of it moving with different attitude and velocity. To send up a single sattelite or a hundred or a thousand would not be able to deal with the situation. Everything that you have ever read about this topic has been conservative at best. It is so out of control that they are now trying to launch a PR campaign (this sattelite) to try and look mildy responsible.
The biggest problems are larger pieces of debris (over 10cm), since they have enough inertia to plow right through our functioning sattelites. So its over 10cm, and moving at tremendous velocity. How the hell do they think they are going to catch it for one (radar is accurate, but accurate down to cm? mm? no way) and the amount of force required to deccelerate the object would quickly deplete the fuel reserves of the spacecraft.
Additionally there isn't very much to be gained by decellerating debris anyway. Changing its inclination yes, but slowing it down? I can't see how that would help at all. Debris under about 1000km usually exits (unless its abnormally dense) in 25-30 years anyway (which is the current NASA NPD).
Probably the best thing that anyone can do (and they are doing it)is to monitor current programs and make sure they won't produce MORE debris. This way in a few years (40 or so) the biggest and most dangerous debris will have burned up, and we will have less debris to deal with.
For more information check out orbitaldebris.jsc.nasa.gov, that is the website for the Code QS program that tries to monitor current spacecraft and make sure they are compliant with the new guidelines. There is also a quarterly OD newsletter there.
Whatever happened to the day when hard-working middle-class American garbagemen used to get rid of our garbage? I think it's unfair to replace these fine souls with these robotic monstrosities. I would much rather see this money used towards finding ways we can send the garbagemen we already have into space to do this job rather than rendering them obsolete as the rest of mankind enters the space age. Nothing this robot does is beyond the capacity of humans.
Garbagemen (and women) of the world, unite against obsolescence! Fight for your right to work in space!
Donny
Gotta say that I agree. Since the vast majority of launches so far has been from France, Russia, and the USA, we should pitch in to cover most of this cost.
I'm not big on glabalism, but unless one country or another decides to "claim" space (an unpopular move, to be sure), I think an international treaty of space exploring nations would be a Good Thing.
We could form a controlling body, and call it DIAOSC (for "DIAOSC Is An Orbital Satelite Committee").
Information wants to be anthropomorphized.
No, all objects in a stable orbit at the same altitude share the same velocity. The shuttle is not in a stable orbit... it goes up, then it comes back.
Also, being at the same velocity does not protect objects who's paths intersect. By your logic, you could safely drive on the wrong side of the highway, as long as you were going the speed limit.
Information wants to be anthropomorphized.
Cleaning the space junk up now is cheaper than not letting it go during the early days of space travel. If we can put it off another decade, it will probably become even cheaper. Costs of orbital space missions have gone down considerably in the past 40 years.
Information wants to be anthropomorphized.
I don't think so. Most satellites are one of kind. There are a few companies that have put out spacecraft "buses" that are the same, but the payloads are different. The cost of putting someone/something up in the orbit to collect all the piece and build something new with them would be _much_ greater than the cost to just build something new. Satellites and space vehicles are non-trivial to build...that's why they cost so much on the ground. Recycling parts is a pipe dream at this point.
At £100,000 each, I can't see how such a system would be practical for cleaning up "space debris." Since each satellite that attatched itself to the debris would burn up in the atmosphere, we would have to produce hundreds or thousands in order to see any effect. There must be a better way to eliminate such debris.
Right now, it costs an insane ammount of money to launch a spacecraft. As I'm sure you all know, the more it weighs, the more it costs. Some sattelites can cost upwards of $100 Million or more to launch. I read somewhere that almost *all* of the costs asociated with SpaceFlight is attributed to getting the stuff of the ground in the first place.
;-) Not to mention that any metalwork that you do would be *perfect*, or darned near close to it, since you're doing it in zero-g. When it reforms, it would be uniform. Yes, I know that all things melted would turn into spheres in space. So, you melt it once, let it cool, and then heat it up enough to make it pliable.
So it's really mind boggling that they want to destroy all this so-called *junk*.
How may of the these so called "non-functioning" sattelites have functional, or close to functional rocket motors? How about fuel tanks that weren't all the way depleted. Or solar panels, or computer chips. Granted, some of the technology is outdated, okay most of it is outdated. But still, it's already *there*. No expensive launches, no planning, nothing. Need a solar panel, grab it off that sattelite over there, need a new hull, rip a section off that one over there. Wanna hook a rocket motor to it, grab it from there. Hey look, that sattelite still has some fuel left, grab it's fuel tank.
Need to do any welding, metal work, just use the sun. It's already 350+ degrees in the sun, just imagine how hot it would be if you amplified it. Gives burning ants in the sun with a magnifying glass a whole new meaning.
There's plenty of computer equipment out there to use in whatever it is that you build. Want to send a mission to the moon, you could do it for FAR cheaper by recycling what is already there, than to build it on the ground and ship it up.
Just imagine how fast and cheap they could build a space station, deep space probes, lunar mining equipment, orbital maneuvering vehicles, etc.. NASA is always going on about being smaller, faster, cheaper. Well you don't get any cheaper than almost free. Besides, aren't they always talking about the three R's. Reduce, Reuse, Recycle.
Perhaps they should start listening to what they've been preaching.
Pete...
I don't understand why they are burning up $100,000 satellites just to take out trash. Why not build a more expensive satellite that can stay up longer? Would it be possible for one of these satellites to catch the trash, picking up a boost of energy, while deacclerating the garbage? How about a cheap ion engine to keep it in orbit, and a couple of solar panels? Sure $100,000 may be cheaper then an ordrinary satellite, but that isn't including the cost of launching these buggers, and it's still a heck of a lot more expensive then the trash itself - and there is a lot of trash.
-- perl -e'print pack"H*","6e656d6f406d38792e6f7267"'
This (Post-Flight Inspection of STS-90) is from NASA Orbital Debris Quarterly News:
Using samples collected by tape pull, dental mold, and wooden probe extraction techniques, a scanning electron microscope (SEM) equipped with energy dispersive X-ray spectrometers (EDXA) were able to identify the nature of 29 of the impactors. A total of 16 particles (55%) were found to be man-made debris, while the remaining 13 particles (45%) were meteoritic in nature. An analysis of the orbital debris impactors revealed an assortment of aluminum (56%), paint (31%), and stainless steel (13%) projectiles.
---
The FAQ from this site says:
8). Does the U.S. Space Shuttle have to dodge orbital debris?
Whenever a Space Shuttle is in orbit, the U.S. Space Command regularly examines the trajectories of orbital debris to identify possible close encounters. If another object is projected to come with a few kilometers of the Space Shuttle, the Space Shuttle will normally maneuver away from the object, even though the chances of a collision are only approximately 1 in 100,000. This occurs infrequently, about once every year or two.
You are not a beautiful or unique snowflake -- but you could be if you got off your ass.
If you notice, the Earth now has a ring similar to that of Saturn. With all this debris, finding an affordable commercial space solution will not be the only problem. It would be no good to see Titanic revisited. Just as icebergs are a problem at the turn of the century, space debris will be a problem during this century.
Pax Digitalia
Launches are very expensive. The Pegasus, which is one of, if not the lowest cost launch, runs at about 11 Million US. It could, though, pack quite a few of these birds on it. I wonder about the satellites' maneuvering propellant margins...
As satellites become smaller and more capable, not to mention cheaper, this places a downward pressure on launch costs. IMHO, this product is a bit premature, as the cost of getting it up is greater than the cost of acquisition.
The only current way to mitigate launch cost is hitching a ride along with another satellite. This causes porblems (ask the OSCAR guys.) As an example, you need a special dispenser that releases multiple payloads in such a way that they enter their proper orbits and don't come into contact. This technology is rather close to a piece of ICBM tech...
It is important, though, to try to clean up the orbit areas if we want to establish any real long-term orbital presence. the threat to hardware (and, eventually, wetware) is too ugly to ignore.
Would we need an entire spaceship to get all the damned unused AOL CDs off the planet? I mean, you can only use so many of them as coasters before they end up in the garbage. If everyone in America got 15-20 of those like I have, it'd take a couple of rocketships to get the billions and billions of wasted space off the ground. Still, they make effective weapons if you just sharpen the edges a little bit. Sharkey
www.badassmofo.com
I'm surprised the US government hasn't invested in these babies to take out the occasional spy satellite:
Mission Control: Sir, the nanosatellite is now in position...
The commander puts his coffee down on a red button sticking up from the panel. Suddenly the nanosatellite attaches itself to a Soviet spy satellite
Commander: Ooooops. I didn't mean to do that. It was an accident, I swear! I'm just going to call my commanding officer and tell him that the mission was a succ.... I mean, that I should be demoted in rank for wasting a 100000 dollar piece of equipment... yes, that's it...
Malfunctioning satelites in a high orbit could be cheaply brought to low earth orbit where they could be repaired. This might generate more revenue than finding someone willing to pay to clean up old boosters.
If even that fails to generate revenue there are always other less nobel options: Pay us 10 milion or your 100 M satelite is fish food.
I wonder if these things are accurate enough to target Redmond?
134340: I am not a number. I am a free planet!
Actually, most stuff under ~750 km altitude will decay all by themselves within 25 years or so, give or take a solar cycle. Even big stuff. Stuff above that altitude is going to be around there longer, but under 750 km altitude is where precious things like shuttle, station, and hubble lay, so that's where the most concern is.
NASA has recently imposed requirements that all satellites deorbit within 25 years, either coming back to earth, or being boosted up to above 1400 km (iirc).
Also, there are a LOT of satellites way, way out at GEO. But these are spaced so far apart that we generally merely boost them up to a slightly higher orbit and leave them there. There is no drag at GEO so no fear of seeing them run into other stuff.
On the positive side, the smaller an item is, the quicker it de-orbits due to atmospheric friction. For example, a cloud of dust (or sand) would de-orbit from LEO within a couple days. It's all about altitude.
Techically, it's a function of altitude, mass, and surface area. Solar cycles play a role as well; when we're in a solar max condition (lots of sunspot activity), the atmosphere "thickens" and thus spacecraft are subjected to stronger drag forces and will decay faster. Surface area is very important. At the end of life we'll feather a spacecraft's solar arrays to maximize atmospheric impingement, and thus go down faster.
OMV is not tether-based, btw. (I work with the guys that designed it, and they are always pulling out the little models and such. *Grin*) In any case, all you need is surface area, so if you wanted to do something fancy, consider just hooking on a big inflatable sail dohicky - cheap, low mass, and effective.
If you have the power to spare for a tether, I'd wonder if it wouldn't be simpler to just use electric propulsion; for a few hundred watts and a few tens of kilograms (and a year or two) you can deorbit most anything. Getting back up out of the drag well would be challenging if you wanted to reuse the orbit maneuvering craft. Probably better to just deorbit the whole mess. But if a spacecraft operator is on contract to deorbit a spacecraft, they generally like to get it done ASAP, and having to wait a few years for a slow deorbit can be expensive.
But the fact of the matter is that most of the garbage up there is *tiny* - bolt heads from old explosive bolt mechanisms, pieces of tape or foil, and bits of metal from explosions or impacts. Small teeny stuff.
OK I was one of the team at SSTL that built that satellite, and it's probably time to set some of the record straight :)
;)
First junk busting is not entirely why we built SNAP. It's main application areas are:
1. Remote inspection: You throw it out of a space station to inspect damage etc.
2. Inferometry: You fly a bunch of them in formation to simulate a big dish/lens.
3. Space science: Fly a number of them to get multiple readings of something like the magnetosphere at each point in time. So you get both time and space measurements.
4. Satellite deorbiting: A SNAP spacecraft with large fuel tank could be used to track down and latch onto a dead satellite, then bring it down.
Now SNAP-1 is just a technology demonstrator. We're proving all the new miniaturised computer/transmitter/camera/propulsion systems actually work. That's why no-one has bought it, cuz it ain't for sale. We do obviously have people in contract negotiations with us to buy their own versions of the SNAP spacecraft.
So to sum up. SNAP-1 is a completely functional spacecraft in a 30cm diameter package. That's quite an impressive feat to pull off. We're flying SNAP-1 on the 28th June 2000. It's probably just got to the launch site as we speak. Once we've proved it works customers will then come to ask us to build new SNAP spacecraft for their particular missions.
It seems all our websites are slashdotted so I wont give any URLs
Richard Lancaster
Journey to Yandol
No Laughing Allowed!
The answer to removing large pieces of junk from orbit is to send up a couple of tether-based OMVs to do it automatically.
Space tethers are basically conductive cables, maybe a mile long or more, that are suspended out of an orbiting vehicle. Because of gravitational gradients, the cable will align itself to be pointing down towards the ground. As the cables pass through the Earth's magnetic field, they convert velocity for energy, producing lots of electricity. It's like an electric motor.
Normally.
If, on the other hand, you run power through the cable, you trade electricity for velocity. Again, like an electric motor.
The end result is that you have a method of altering your orbit that doesn't require expending propellents. This technology will be installed on the Mir space station late this year or next, ending the reliance on Progress boosters.
Anyhow, the reason I'm bringing this up is that this is the key to removing big debris.
You launch an orbital maneuvering vehicle that uses this technology. It would rendezvous with the piece of debris and turn on the orbital brake (eg, use the tether to start generating electricity) until the object was on a re-entry vector, then it would detach and use the tether to raise itself to the orbit of the next piece of large debris.
The process could be mostly automated and wouldn't require expending propellent. Gyros would provide attitude control (and maybe energy storage for nighttime passes).
Of course, this only takes care of the stuff that's big enough to be tracked.
On the positive side, the smaller an item is, the quicker it de-orbits due to atmospheric friction. For example, a cloud of dust (or sand) would de-orbit from LEO within a couple days. It's all about altitude.
I knew Iridium would turn out alright!
Drag n' Drop DVD Recommendations
I remember a gentleman from NORAD come to my school about 4 or 5 years back to discuss what exactly they did up there. One of the facts that they gave us was that they were (then) tracking over 65,000 objects in and around earth's upper atmosphere. Most of it man made trash.
:P
When you realize that if one of these hits a satelite or (worse) space, shuttle...at the velocity it's going...it would basically tear a hole right through it.
I think in the best of all possible worlds, the U.N or some other international organization would get together to find the funds for something like this. It's getting pretty cluttered up there, and i don't want to have to see a whole bunch of garbage when i take my scenic trip to the moon in 2014.
FluX
After 16 years, MTV has finally completed its deevolution into the shiny things network
"It is seldom that liberty of any kind is lost all at once." -David Hume