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Giant Balloons Could Solve Space Junk Problem

samzenpus posted more than 4 years ago | from the giant-balloon-animals-soon-to-come dept.

Space 210

An anonymous reader writes "More than 100,000 objects bigger than a centimeter wide hover around our planet, accounting for 4 million pounds of junk that befouls our atmosphere and threatens the expensive satellites we actually want in orbit. Dr. Kristen Gates, of Global Aerospace Corporation, proposes that we can clear the skies by attaching a football field-sized balloon to dead satellites, which would increase the orbital drag, eventually bringing a satellite down into the atmosphere where it would burn up. The GOLD — or Gossamer Orbit Lowering Device — unit is easily inflated in space, and best of all, if the deployed GOLD balloon collides with space junk, it won't deflate or break the junk into smaller, less manageable bits."

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pop! (1)

Hatta (162192) | more than 4 years ago | (#33144870)

If there's enough junk flying around up there to damage satellites, wouldn't it also pop a giant balloon?

Re:pop! (4, Interesting)

h4rr4r (612664) | more than 4 years ago | (#33144894)

With no pressure on the outside of the balloon it would deflate very slowly. This is doubly so because it does not take much gas to inflate a balloon in space due to the lack of outside pressure.

Re:pop! (3, Interesting)

teeks99 (849132) | more than 4 years ago | (#33144952)

Also they have developed materials that, once inflated in the vacuum of space, can hold their shape without any internal pressure.

Yes, but can they make the surface sticky? (2, Funny)

ben2umbc (1090351) | more than 4 years ago | (#33145502)

Ok, now that you have a huge football field sized balloon, why not make the outside surface sticky and collect other bits of space junk on the way to the burn?

Re:Yes, but can they make the surface sticky? (1)

iksbob (947407) | more than 4 years ago | (#33145550)

The differences in velocity are generally too great. It would be like trying to stop a shotgun blast with a single layer of packing tape. If you're lucky, a tiny speck of the tape might stick to a few of the pellets as they shred the strip and continue on their way.

Re:Yes, but can they make the surface sticky? (2, Insightful)

Brad1138 (590148) | more than 4 years ago | (#33145674)

The differences in velocity are generally too great. It would be like trying to stop a shotgun blast with a single layer of packing tape. If you're lucky, a tiny speck of the tape might stick to a few of the pellets as they shred the strip and continue on their way.

Sounds like a new Myth Busters episode...

Re:Yes, but can they make the surface sticky? (3, Interesting)

ushering05401 (1086795) | more than 4 years ago | (#33146200)

I wonder if you could coat the balloon with a cheap reflective material that would leave residue on debris that impacted the surface. Wouldn't that provide a gradual increase in our tracking ability without costing a whole lot more than the original design?

Re:Yes, but can they make the surface sticky? (1)

MadnessASAP (1052274) | more than 4 years ago | (#33145562)

Because when the space junk is a bolt traveling at 10km/s relative to you, sticky doesn't quite cut it.

Re:Yes, but can they make the surface sticky? (5, Funny)

h4rr4r (612664) | more than 4 years ago | (#33145564)

Because it will never catch them?

You can test this at home with this simple procedure.

1. Get a sheet of mylar and some sticks, an emergency blanket will do.

2. Using the mylar and some sticks make a your balloon. The sticks will help to simulate the structures that can hold their shape.

3. Tie this off to any structure. That structure will be the stand in satellite.

4. Cover the balloon in glue.

5. Get out your favorite high power firearm and fire some rounds at the balloon. These will be the space junk.

6. see if any bullets, your simulated space junk, got stuck in the glue

Re:Yes, but can they make the surface sticky? (1)

dakameleon (1126377) | more than 4 years ago | (#33146220)

Step 5 gave me the biggest belly laugh I've had this year. Thank you, sir!

Re:pop! (0, Redundant)

commodore64_love (1445365) | more than 4 years ago | (#33145034)

Bigger issue: We have to send astronauts out in space to tie balloons to all this junk, one at a time. So..... wouldn't that cost a heck of a lot of money in terms of man-hours? Hmmmm. Maybe it's a job stimulus bill - the first space garbage men.

I wish humans would be longer-sighted. They should have designed these satellites to be self-killing - i.e. Burn a rocket, deorbit, and burn rather than just throw stuff all over the place & forget about it.

Re:pop! (1)

h4rr4r (612664) | more than 4 years ago | (#33145066)

What part of this requires astronauts?
It sure seems that a robot could well tie a string around something, or a velco band or whatever they use to attach space balloons.

Re:pop! (0)

Anonymous Coward | more than 4 years ago | (#33145094)

yea nasa cant even make a robot climb over a rock, what makes you think they can have one floating around in space making knots

Re:pop! (1)

h4rr4r (612664) | more than 4 years ago | (#33145158)

Because no knots are required, only a high friction tape/string and many windings.

Re:pop! (2, Funny)

camperslo (704715) | more than 4 years ago | (#33145260)

No Astronauts needed, just one Battery Operated Rubish Gatherer (BORG)

Re:pop! (1)

Conditioner (1405031) | more than 4 years ago | (#33145322)

If they have a robot that is up there tying knots, wouldn't it just be smarter to have the robot push/throw the junk downwards in to the atmosphere ?

Re:pop! (1)

h4rr4r (612664) | more than 4 years ago | (#33145396)

How do you propose they do this, considering newtons laws?

Re:pop! (1)

teeks99 (849132) | more than 4 years ago | (#33145098)

The most important part is to get a system working for future spacecraft (and rocket stages) that are going up. Once that is solved, then we can go and work on the stuff that is already up there.

I think that this balloon could be attached to a lot of space junk with a (very small) robotic space craft of its own. That robotic craft could use gps and cameras to rendezvous with the debris, then some type of manipulator arm could grab onto the debris. Since the force applied by this balloon would be *VERY* small (but applied over a long period of time - months) the bond between the two spacecraft wouldn't have to be very strong.

Re:pop! (1)

fsterman (519061) | more than 4 years ago | (#33145116)

Bigger issue: We have to send astronauts out in space to tie balloons to all this junk, one at a time. So..... wouldn't that cost a heck of a lot of money in terms of man-hours?

Super glue is cheap.

Re:pop! (2, Funny)

DougF (1117261) | more than 4 years ago | (#33145900)

Sandford and Son in Spaaaaaaace?

Collision course (1, Informative)

DeadDecoy (877617) | more than 4 years ago | (#33144880)

The question isn't just whether it can collide with and bring down space junk, but whether it can avoid legitimate satellites as well. I guess if anyone has any secret spy satellites floating around they better speak up or lose them to an uncoordinated balloon collision : ).

Re:Collision course (2, Insightful)

h4rr4r (612664) | more than 4 years ago | (#33144916)

How can satellites be secret? Either they are highly reflective and everyone can see them or they are going to be very warm.

Re:Collision course (1)

abelenky17 (548645) | more than 4 years ago | (#33145064)

While it is true you can stare up in the sky and spot certain satellites with the naked eye, and even more with telescopes and equipment, thats not the whole story.

To know the full path of a satellite takes multiple, precise observations over time along with some detailed calculations, and that is ONLY if the satellite is stable.

Many of the most secretive satellites regularly adjust their orbits with thrusters. So if you get lucky enough to spot it and calculate an orbit, it may move to a new orbit soon.

Hence, the number, position, and trajectory of many government satellites is "secret" even if they are in plain view.

Re:Collision course (3, Informative)

teeks99 (849132) | more than 4 years ago | (#33145134)

Actually most spacecraft (including "secret" government satellites) are tracked by both governments and private entities. Since the last collision the US Air Force has actually started expanding their capability for this even more. They are very open to working with other parties to solve space debris issues and avoid collisions with their satellites or between other satellites.

Re:Collision course (1)

h4rr4r (612664) | more than 4 years ago | (#33145172)

Please name one satellite that has done this. I have a hard time believing any of them have enough fuel to change orbit repeatedly.

Re:Collision course (1)

teeks99 (849132) | more than 4 years ago | (#33145228)

Many satellites change their orbit...because of the speeds they are moving, distances covered, etc. even a small change in orbit can mean that a day or two later you're in a completely different part of the world than where you would have been, had you not done anything. The space station does this all the time, they routinely move 100mi or more over the course of a day or so to avoid space debris. Other, smaller, satellites do this too, however there are also many that don't have engines on them and can't really move themselves.

Re:Collision course (1)

h4rr4r (612664) | more than 4 years ago | (#33145306)

The space station, is a fine answer. Unlike other satellites it does get fuel resupplies though. Is there a place I can see how much sats change orbit?

Re:Collision course (0)

Anonymous Coward | more than 4 years ago | (#33146230)

The space station, is a fine answer. Unlike other satellites it does get fuel resupplies though. Is there a place I can see how much sats change orbit?

Yeah. How are you in near vacuum conditions?

Re:Collision course (3, Insightful)

Martin Blank (154261) | more than 4 years ago | (#33146044)

abelenky17 is off-base. The ones most likely to be of interest are also the largest (and generally most-capable) units, which would require the most fuel to move. Mercury SIGINT satellites are around five tons, and the Lacrosse synthetic aperture radar satellites reportedly mass up to 16 tons, and both are in LEO.

This isn't to say that they cannot change orbits, just that it requires a very good reason to do so, as not only does it use up precious fuel, but like any operational satellite it has scheduled uses. They're never put up there "just in case we need them."

It's also not to say that there is no use for highly-variable orbits. That the Air Force has been playing with their recently-launched toy shows as much. It's just that such things are not trivial achievements. Such capabilities make it much harder to hide from overhead eyes. Lacrosse-5 has some kind of technology that allows it to "disappear" even in direct sunlight, which makes much more sense than loading it with tons of fuel, but still leaves it fairly predictable.

Re:Collision course (1)

kimvette (919543) | more than 4 years ago | (#33146262)

But. . . but. . . this is done every day. A US Air Force commercial [youtube.com] told me so!

Re:Collision course (1)

element-o.p. (939033) | more than 4 years ago | (#33145082)

In which case, you can still see them (at least in IR).

Re:Collision course (2, Informative)

sznupi (719324) | more than 4 years ago | (#33145150)

It doesn't sound like it's meant to bring down some random spacejunk with which it collides (which would mostly pass through it after all, at best / if impacts won't produce more debris), just to bring down a satellite to which it is attached. Not the only effort of such kind [surrey.ac.uk]

Re:Collision course (1)

jmv (93421) | more than 4 years ago | (#33145314)

That was my first thought: "to fight space junk, we'll just send more space junk".

I hope (0)

Anonymous Coward | more than 4 years ago | (#33144882)

the good doctor didn't get paid to come up with this

And all you need to do is catch up to the debris.. (2, Insightful)

sargeUSMC (905860) | more than 4 years ago | (#33144906)

Easy-peasy. No delta-V issues here...

Re:And all you need to do is catch up to the debri (2, Informative)

Anonymous Coward | more than 4 years ago | (#33144936)

Naturally the slashdot headline is wrong. They're talking about attaching it to entirely intact satellites to get them to de-orbit without hitting something and making more debris. (as seen from the URL of the story linked: "_Without_Making_The_Problem_Worse"

In other words, you just have to catch up to the satellites.

Does it mass more than the fuel to de-orbit? (1)

rbrander (73222) | more than 4 years ago | (#33144940)

When The Economist magazine became the first general-interest magazine to cover the space junk problem about 15 years ago, it pointed out that the problem was there was no international agreement or agency forcing private owners of satellites to budget enough fuel to de-orbit the satellite at the end of its life. Every gram costs a small fortune, so they used every gram of fuel to keep the satellite "stationary" (i.e. in desired orbit).

The space junk problem (except for paint chips and astronaut toolbags) nearly ceases to exist if everybody would just de-orbit their property. I find it hard to believe that the mass of a football-field-sized balloon is less than the fuel to just drop the orbit into a brief but colourful brush with the atmosphere.

Re:Does it mass more than the fuel to de-orbit? (2, Interesting)

MichaelSmith (789609) | more than 4 years ago | (#33145014)

I find it hard to believe that the mass of a football-field-sized balloon is less than the fuel to just drop the orbit into a brief but colourful brush with the atmosphere.

Well you need to factor in the rocket engine, guidance, and the risk that you may lose active control of the vehicle and be unable to deorbit it. My thinking is that a drag brake (or parachute, solar sail or balloon) could be a separate system. Mostly passive. It gets a simple command, or fires on a timer. It orients itself passively and results in re-entry in a couple of months or so.

Re:Does it mass more than the fuel to de-orbit? (1)

teeks99 (849132) | more than 4 years ago | (#33145054)

Yeah, the simpler the system, the better. Unfortunately parachutes and solar sails require the spacecraft to control what direction they are pointing in...that's why I like balloons for it, because they are spheres and work the same from every direction.

Re:Does it mass more than the fuel to de-orbit? (1)

nospam007 (722110) | more than 4 years ago | (#33145342)

Wouldn't a couple of miles long ribbon do the same thing with less tech?

Re:Does it mass more than the fuel to de-orbit? (1)

teeks99 (849132) | more than 4 years ago | (#33145354)

I think the ribbon would just end up moving to being in a line behind the satellite along the path it just came from in orbit...think of how a ribbon follows behind a car...in its slipstream. Anyway, being behind the satellite doesn't really help increase drag, so it wouldn't help bring it down quicker.

Re:Does it mass more than the fuel to de-orbit? (2, Insightful)

russotto (537200) | more than 4 years ago | (#33145552)

A ribbon will actually end up perpendicular to the satellites orbit, due to tidal effects.

Re:Does it mass more than the fuel to de-orbit? (1)

teeks99 (849132) | more than 4 years ago | (#33145628)

Only if it has substantial mass. If it is a low mass device, than the drag on it will make it parallel (behind) the satellite.

Re:Does it mass more than the fuel to de-orbit? (1)

Laser Dan (707106) | more than 4 years ago | (#33146290)

A ribbon will actually end up perpendicular to the satellites orbit, due to tidal effects.

Actually that might be a good thing. I read somewhere about attempts to power satellites by dragging a long wire, the movement through the earth's magnetic field produces a current. The problem was that because of the magnetic drag, more fuel was required to keep the satellite in orbit.

So for an end-of-life satellite, simply releasing a long wire may be enough to de-orbit it without requiring more fuel. I think the wire had to be very long (but thin) so the mass wouldn't be too excessive. If it still takes a long time to de-orbit though, instead of chunks of metal in orbit you have chunks with long invisible wires hanging off them, which could be even more dangerous.

Re:Does it mass more than the fuel to de-orbit? (1)

teeks99 (849132) | more than 4 years ago | (#33145016)

This mass of a giant balloon could actually be incredibly small...on the order of 10lbs. This would almost certainly be lighter than the amount of propellant needed to deorbit. The down side is that with propellant you could be down in a matter of days, the large balloon could still take months.

The other nice part about a balloon is that its roughly spherical...so you don't have to worry about what direction the spacecraft is pointing. This isn't a problem for spacecraft that already have guidance/engines for them...just add more propellant, but some spacecraft don't have guidance/engines so you'd have to add a lot more than just propellant.

Re:Does it mass more than the fuel to de-orbit? (2, Insightful)

commodore64_love (1445365) | more than 4 years ago | (#33145122)

>>>Every gram costs a small fortune, so they used every gram of fuel to keep the satellite "stationary" (i.e. in desired orbit).

It's pretty pathetic that despite 50 years of space experience, we still have to worry about mere grams of fuel. I suspect humans will never develop the ability to travel further than our own solar system - it would be too expensive (in terms of fuel).

1000 years from now we'll be in pathetic shape, with all our oil, uranium, and other resources drained dry, and just barely surviving. Never mind space travel. There won't be enough fuel for the rockets. ----- I also suspect this is why we've never been visited by aliens. They can't escape their own solar system due to lack of energy.

Re:Does it mass more than the fuel to de-orbit? (0, Offtopic)

UnknownSoldier (67820) | more than 4 years ago | (#33145476)

Gee, aren't we the optimist.

> I also suspect this is why we've never been visited by aliens. They can't escape their own solar system due to lack of energy.

Never A Straight Answer begs to differ with their own photage. Evidence: The Case For NASA UFO's.

Part 1
http://www.guba.com/watch/3000113495/The-Case-For-NASA-UFOs-PART-1 [guba.com]
http://www.youtube.com/watch?v=72P5OtrHNyk [youtube.com]
Part 2
http://video.google.com/videoplay?docid=8524267568796529301 [google.com]

Re:Does it mass more than the fuel to de-orbit? (1)

Columcille (88542) | more than 4 years ago | (#33146030)

"1000 years from now we'll be in pathetic shape, with all our oil, uranium, and other resources drained dry, and just barely surviving."

...since people were just barely surviving in the era before oil, uranium, and other resources were being used. Unless by "other resources" you mean things like trees, food, etc, which are replenishable, or water, which isn't really going anywhere any time soon, even if it's not always at the part of the planet we might prefer.

Re:Does it mass more than the fuel to de-orbit? (0)

Anonymous Coward | more than 4 years ago | (#33145282)

Not all satellites have a means of propulsion. Most are able to orientate themselves, but they do not all contain a propulsion system to provide delta-v.

Re:Does it mass more than the fuel to de-orbit? (0)

Anonymous Coward | more than 4 years ago | (#33145402)

It's more of a liability issue.
If you deliberately deorbit and hit someone or their property you're responsible. If it's an "act of your imaginary friend upstairs" you're off the hook.

The commons... (1)

copponex (13876) | more than 4 years ago | (#33145484)

The perennial problem of common resource management. There is no agreed upon agent that rules earth orbit space. So there aren't any rules. Without rules, the market is just going to take the cheapest route. Most often this includes polluting common resources, because sustainability and responsibility are expensive. Bad for the bottom line.

So the earth people can make a choice: sell all of the corridors to the highest bidder, and hope that they take care of it. Or you tax the industries that want to use those resources in order to pay for a governmental body to keep an eye on them and make sure the rules are followed.

With the first option you just have to hope that the companies won't exploit the resource for short term gain and then leave anyone who uses the same resources with the bill for cleanup. In the second option, the government holds some of the profit back to clean up when the corporation inevitably does something stupid and leaves a mess. Back in the day, they even held company leaders criminally liable for their negligence. Imagine that.

Re:Does it mass more than the fuel to de-orbit? (1)

Kral_Blbec (1201285) | more than 4 years ago | (#33145646)

FTA

Although the ultra thin envelope could be the size of a sports field (100 m diameter) when inflated, it is so thin that it can be folded and stowed in a surprisingly small volume (a medium size suitcase). It is most economical to attach it to a spacecraft or rocket upper stage before launch and deployed after the end of mission.
...
The GOLD system actually weighs less than the propellant needed to do the same job and it is very inexpensive, and this means it is more cost-effective to add a GOLD system before launch than to carry the extra fuel.

giant footballs (1)

Dr Max (1696200) | more than 4 years ago | (#33144956)

I don't know how big footballs are where this guy comes from, but i wouldn't call a football sized balloon giant.

Re:giant footballs (1)

Dr Max (1696200) | more than 4 years ago | (#33145006)

football field sized sorry

Re:giant footballs (1)

MichaelSmith (789609) | more than 4 years ago | (#33145030)

Make it an Australian football field and you've got a deal.

Re:giant footballs (0)

Anonymous Coward | more than 4 years ago | (#33145040)

I don't know how big footballs are where this guy comes from, but i wouldn't call a football sized balloon giant.

"Football-field sized"...a 100-yard diameter balloon is pretty giant.

Instead of a Baloon what about a Net to catch stuf (1)

HockeyGuy (1864828) | more than 4 years ago | (#33144998)

They want to attach a balloon to the end of a satellite to create drag to bring it in and have it burn up...

What about a net that could capture some of the crap up there as it increases drag it would sweep everything clean instead of just bringing in one satellite...

you could even inflate the tip of the net in a disk shape like the top of a balloon to expand the net open to catch stuff

©

Re:Instead of a Baloon what about a Net to catch s (1)

VortexCortex (1117377) | more than 4 years ago | (#33145280)

Using a net like that is like trying to catch bullets not butterflies.
You'll end up with projectiles at orbital velocities punching holes in your net.

Re:Instead of a Baloon what about a Net to catch s (0)

Anonymous Coward | more than 4 years ago | (#33145824)

As other have pointed out in response to other comments, that would be like trying to catch shotgun pellets with strips of plastic wrap.

Re:Instead of a Baloon what about a Net to catch s (1)

petermgreen (876956) | more than 4 years ago | (#33146136)

The problem with trying to catch anything in space is that it is likely to be moving in a different direction to you and since its in orbit it will be going very fast. So the combined speed in any collision between your object and a peice of space junk is likely to be extremely high (afaict orbital velocities make bullets look slow). The space junk would most likely just punch a hole straight through your net.

That is why space debris is such a hazard in the first place.

Pounds ??? (1, Insightful)

Anonymous Coward | more than 4 years ago | (#33145018)

WTF is "pounds" ?

Science Channel already covered this... (0)

Anonymous Coward | more than 4 years ago | (#33145086)

http://www.youtube.com/watch?v=6Fy7psIuJjc [youtube]

This just might be stupid enough to work (2, Funny)

uglyMood (322284) | more than 4 years ago | (#33145092)

If you could find a way to make the exterior sticky as it's being deployed, then anything in a similar orbit and speed would be swept up as well. And I shall call it... The Space-Swiffer!

Re:This just might be stupid enough to work (1)

kimvette (919543) | more than 4 years ago | (#33146310)

Dear uglyMood

We (Swiffer USA) are the owner of trademark registration no. 349r84735987349. Details of this registration are set out on the attached schedule, marked "A".

Widespread use of the Swiffer(R) trade mark has been made, to the extent that this trademark has acquired an extensive reputation and goodwill. The Swiffer trademark is, accordingly, also a well-known mark for all relevant purposes of trademark law.

It has come to our attention that you are using and/or have applied to use and publicize the Swiffer trademark.

This trademark is an infringement on our Swiffer trademark and also constitutes a reproduction or imitation thereof.

In the circumstances, your use of the Swiffer trademark will constitute an infringement of our registered and common law rights.

In the circumstances, we demand that you immediately:

1. cease all use of the trademark Swiffer;

2. deliver-up for destruction all material to which the Swiffer trademark or any other mark confusingly or deceptively similar to our trademark has been applied;

3. withdraw, cancel and/or delete any corporate names, domain names, trademark applications and/or trademark registrations for or including the Swiffer trademark;

4. undertake, in writing, never in future to make any use of the Swiffer trademark without prior written authority from us, whether within any corporate name, trading name, trading style, domain name or otherwise.

We await to hear from you by no later than close of business on Septober 32, 4921.

This is written without prejudice to our rights, all of which are hereby expressly reserved.

Yours faithfully,

Swiffer USA shark department.

Gossamer Orbit Lowering Device (1)

SnarfQuest (469614) | more than 4 years ago | (#33145132)

Gossamer Orbit Lowering Device

With such evocative words in the name, like gossamer and gold, are you sure this isn't just a giant condom?

easily inflated in space

Doesn't change my mind yet...

it won't deflate or break the junk into smaller, less manageable bits.

Umm, still sounds gross...

Or sail... (1)

sznupi (719324) | more than 4 years ago | (#33145136)

"CubeSail" for example; soon available for deployment - http://www2.surrey.ac.uk/mediacentre/press/2010/26099_a_mission_to_clear_dangerous_debris_from_space.htm [surrey.ac.uk]

Should make some nicely visible light show from time to time...

Re:Or sail... (1)

teeks99 (849132) | more than 4 years ago | (#33145176)

They should have a competition....launch a bunch of micro-satellites...one with a sail like surrey's, one with a balloon like this article, one with a small rocket, and one with nothing special on it....then the first one to burn up wins!

Help (4, Funny)

Kozar_The_Malignant (738483) | more than 4 years ago | (#33145194)

I'm having a problem understanding how filling low-earth-orbit with Zerg Overlords is a good thing.

Befoul our atmosphere? (1)

by (1706743) (1706744) | more than 4 years ago | (#33145204)

TFA:

...accounting for 4 million pounds of junk that befoul our atmosphere...

Uh...wouldn't said "junk" be falling to earth pretty soon after entering our atmosphere, what with drag and all?

Why not collect it in space? (3, Insightful)

richardkelleher (1184251) | more than 4 years ago | (#33145232)

What I don't understand is, since we already paid a hefty price to lift this "material" into space, why not collect it in orbit and save it until we can utilize it as raw materials for future space projects. There must be lots of useful stuff that could be reprocessed and reused.

Doesn't everyone have the expectation that we will have factories in space to build the things that are needed in space from raw materials gathered from around the solar system? This would just be raw materials for those factories that doesn't have to be lifted out of the gravity well of earth.

Re:Why not collect it in space? (2, Insightful)

geekoid (135745) | more than 4 years ago | (#33145398)

In most case you would spend more then you could possible get out of bringing it back.

Re:Why not collect it in space? (2, Informative)

SixAndFiftyThree (1020048) | more than 4 years ago | (#33145406)

1. Launch costs will have to come down by a hefty factor before it becomes economic to launch entire factories and bring raw materials from far away. Once launch costs have come down that far (and I'm not holding my breath), the value of the raw materials that are in orbit today will seem slight. Meanwhile, even one more collision between derelict satellites will make the orbital environment more dangerous and harder to clean up.

2. The raw materials that are in orbit today are in a wide variety of orbits, by both altitude and inclination. If your factory is in equatorial orbit, the delta-V needed to collect a given mass from a polar or near-polar orbit (which spysats tend to use) is more than the delta-V needed to launch it from Earth, and far more than the delta-V needed to launch it from an asteroid etc.

Re:Why not collect it in space? (2, Insightful)

VortexCortex (1117377) | more than 4 years ago | (#33145414)

Why not collect it in space?

It's not economically feasible to collect it, but you might like Planetes [anime.com] - an Anime about collecting space junk in exchange for eco-friendly credits (like carbon offsets).

Re:Why not collect it in space? (1)

richardkelleher (1184251) | more than 4 years ago | (#33145800)

If we have to send something (or someone) to each major object of space junk to attache one of these decelerators, how would collecting the object be less costly?

Re:Why not collect it in space? (5, Informative)

Rich0 (548339) | more than 4 years ago | (#33145946)

Ok, you've grappled the object. Where do you want to send it?

Sending it down requires a drag chute of some kind. Or it requires just enough delta-v to drop its perigee just a little lower into the atmosphere.

Suppose we had the mother of all factories sitting in equatorial orbit. Suppose your space junk is in a 35 degree orbit. Both objects are traveling at around 27Kkm/h if they're in a relatively low orbit. However, one object is moving 27Kkm/h due east, and one is moving 27Kkm/h 35 degrees north of east. Relative to each other they are moving at thousands of kilometers per hour when they pass each other. To collect the object you need to apply that much of a velocity change to it, which is a huge amount of energy (not quite what it took to launch, but we're getting into that kind of magnitude).

Think of it this way - you're on a racetrack going 200mph. Another car is going 200mph the other way. You want to collect it. How do you do this without massively changing its velocity?

One of the first rules of orbital mechanics is that plane changes are expensive. That's why the shuttle can't visit the ISS and the hubble on the same mission. They're both in similar altitude orbits, but in different planes. The shuttle doesn't have enough fuel to change planes (at least, not that far - and without looking up the numbers that is probably only 10 degrees or so).

Re:Why not collect it in space? (1)

socsoc (1116769) | more than 4 years ago | (#33146026)

It's equally as useless as your original post. It's junk for a reason, just like how people throw out bottles with redemption values. Fuck the raw materials, it's gonna be old technology and metals nobody cares about.

Weird.... (1)

BJ_Covert_Action (1499847) | more than 4 years ago | (#33145250)

I don't see why it needs to be an inflatable balloon. If the goal is to produce drag to decrease your orbit until reentry, why not just deploy a very large, football field sized tether and sail to the back. The material demonstrated by the Ikaros mission for use in a solar sail could do something like this. Carrying an inflatable balloon and the gas necessary to inflate it seems like over-complicating the very simple goal of increasing drag. As for deployment, tethers can do some pretty cool deployments simply by using the angular momentum of a spacecraft over a very long, slow, rotation maneuver.

The balloon idea seems weird.

Re:Weird.... (2, Informative)

teeks99 (849132) | more than 4 years ago | (#33145296)

That's all fine and good if you have great attitude (direction) control of your spacecraft. If you lose your gyros or something during the lifetime of the spacecraft, then you wouldn't be able to control an Ikaros like sail. Having a spherical balloon that doesn't care about direction and can inflate with minimal mechanical effort seems a lot more reliable.

Re:Weird.... (1, Informative)

BJ_Covert_Action (1499847) | more than 4 years ago | (#33145468)

If you've lost control of your spacecraft before it begins it's deorbit maneuver, chances are any system you put on there is going to have a hell of a hard time getting it to deorbit appropriately. Even if you start to inflate this giant spherical balloon after you've lost the ability to point your spacecraft, due to loss of reaction wheels or some other such thing, you are going to be trying to deploy a very large moment arm in an unpredictable/unknowable dynamic scenario (in other words, your rates and attitude will be completely unknown). This is going to inflict some pretty heavy structural loads on your spacecraft, primarily where the deployment system connects to the bus. As such, if you are trying to deploy this giant balloon in anything but the designed for performance envelope, you run the very real risk of tearing the deployment mechanism, and, hence, balloon from the bus, or failing catastrophically in some other manner, which would be completely counter-productive to your attempt to deorbit in the first place.

In short, deploying something this large is not something you just get to do no matter how your spacecraft is behaving. Like any other deorbit scenario, this balloon is going to have a performance criterion requirement that it must be designed for: "At end of mission you must be able to control your spacecraft within X, Y, and Z parameters in order to ensure successful deployment of giant balloon." You will have a similar mission requirement for any other deorbit profile, including a large sail. Now, I will give that those mission requirements might be a bit more lenient for the giant balloon (and I stress might), but I would much rather see a comprehensive trade study that sheds some light on whether or not this theoretical relaxation of mission requirements buys you any performance, fuel-margin, or mass throughout your mission. And I would want to see them compared against the increased complexity of using a balloon deployment as opposed to a tether or sail deployment.

Don't get me wrong, if the fella in the article has done such studies and shown that it will likely increase mission performance, then whether or not I think this is weird, we will see a giant balloon flying on a mission eventually. However, right now this seems like an interesting concept that doesn't seem like it would bring a whole lot to any given mission to me. This speculation is based off little more than my own personal knowledge of deorbiting spacecraft, which is part of the mission analysis that I do for a living.

Re:Weird.... (2, Interesting)

teeks99 (849132) | more than 4 years ago | (#33145676)

If this were air, you'd be completely correct. However, in the vacuum of space and with a very light balloon (we're talking on the order of 10lbs for a football-field size one) there isn't much of a moment arm. The force due to drag would probably be measured in ounces and then you have just the weight of the actual structure. Generally when satellites attitude control systems fail, they don't immediately start spinning like crazy, probably just a few degrees per minute.

Re:Weird.... (1)

prozac79 (651102) | more than 4 years ago | (#33145384)

There was this article [wired.com] in Wired magazine talking about space junk and bringing them down with a giant tether. It seems like the balloon idea might work with large pieces of junk, but it seems like the bigger threat are the small pieces no larger than a few inches. The article stated that the ISS had a few close calls with some pieces of junk no larger than a baseball that could have caused massive damage if it hit the station. We can't tied a balloon or tether to every little piece out there. We need a giant space vacuum like this one! [gstatic.com]

A question? (1)

Mephistro (1248898) | more than 4 years ago | (#33145278)

How does this beat the use of magnetic tethers, also proposed for this task some time ago? Wouldn't the balloon's draft reduce the speed enough for the satellite to survive reentry and fall to earth in a single piece? Or are they planning to free the balloon before entering the first layers of atmosphere?

Just curious.*

*:Yeah, yeah, I'm gonna read TFA. :)

Got her name wrong (2, Informative)

crgrace (220738) | more than 4 years ago | (#33145330)

It's Dr. Kristin Gates [gaerospace.com] . At least try to get the basic facts right.

The same thing will happen without the football. (1)

BitZtream (692029) | more than 4 years ago | (#33145358)

Seriously, if you think this is a good idea you don't understand orbital dynamics.

Anything that is causing drag on the football is intern also causing drag on the hundred times larger satellite it is attached too.

In about 80 to 90 years, that football might have been noticed in fuel used for station keeping, otherwise it won't make a dent in anything that matters.

If the football is going to 'cause drag and eventual reentry' the satellite was going to do that anyway and the 10 minutes that the football brings it in sooner isn't really all that relevant.

Nothing stays in orbit forever, its all either coming back to Earth or heading out into space, its just a question of when it happens in a meaningful way.

Re:The same thing will happen without the football (1)

BitZtream (692029) | more than 4 years ago | (#33145378)

football field ... heh, that changes things slightly.

That just brings us back to 'if you can do something to activate said football field sized balloon ... why not just fire some rockets to lower its obit WAY faster and FAR more CONTROLLED.

If you argue that you may not have control of the sat then I'd like to know how you plan to activate this ballon.

Re:The same thing will happen without the football (1)

Kral_Blbec (1201285) | more than 4 years ago | (#33145828)

As mentioned in the article, even if you have a propulsion system in place the human tendency is to use the fuel to extend the lifetime instead of sending it in a kamikazi mission to deorbit. If the last ounce of fuel can give you either another 6 operating months or deorbit in 2 days, it will be used to get another 6 months.

Not just a balloon! (1)

Sooner Boomer (96864) | more than 4 years ago | (#33145364)

You wouldn't necessarily need to inflate a large balloon. There are several other low-mass/high drag options. A long ribbon would be one. It could be coiled up against the torque of a spring (for example) and be released by mechanical means; a lot simpler than carrying the stuff (valves, hoses/tubing, tanks, etc) to inflate the balloon (even though you would only need a small amount of pressure). There were several experiments with tethers and satellites back in the '90's. Two mechanisms would help bring down the satellite: electrodynamics [wikipedia.org] and gravity [wikipedia.org] .

Use the force instead (2, Interesting)

Anonymous Coward | more than 4 years ago | (#33145388)

The electromagnetic force that is.

Why would you bother with atmospheric drag, just pay out a cable and use electromagnetic drag instead. Oh wait they can do that already...

http://www.technovelgy.com/ct/Science-Fiction-News.asp?NewsNum=264

Use the force instead (1)

nacnud75 (963443) | more than 4 years ago | (#33145420)

The electromagnetic force that is. Why would you bother with atmospheric drag, just pay out a cable and use electromagnetic drag instead. Oh wait they can do that already... Terminator Tether - EDT Solution To Space Debris [technovelgy.com]

A permanent solution, the stratollite... (1)

Ex-MislTech (557759) | more than 4 years ago | (#33145522)

There may be more than one company, but the one I ran across years ago
was 21st century airships.

http://www.21stcenturyairships.com/HighAlt [21stcenturyairships.com]

At 65,000 ft there is no wind.

With almost the same controls as used for RC planes one person
could launch or land a stratollite for repairs or upgrades.

With this lower version of the satellite you could use less power
and get less interference.

You cover less area, but the costs of launch are so much lower
it makes it well worth it and even more if the balloon has multiple
ppl hanging their gear off it.

As cheap as they are they could even have one on standby in a region
for rapid deployment in case one gets in trouble.

Sometimes Low Tech beats High Tech, pun intended.

won't be cheap (0)

Anonymous Coward | more than 4 years ago | (#33145556)

On board prior to launch =OK

Catching up to a 18,000MPH satellite=expensive

Dr. Strangelove has an answer (2, Funny)

russotto (537200) | more than 4 years ago | (#33145576)

Set off a bunch of nukes in the upper atmosphere. This will cause the atmosphere to expand, increasing drag and sending LEO space debris plummeting to earth.

Of course there will be side effects, but hey, it's NUKES.

Re:Dr. Strangelove has an answer (1)

Kaenneth (82978) | more than 4 years ago | (#33145764)

It's the only way to be sure.

Re:Dr. Strangelove has an answer (1)

Greyfox (87712) | more than 4 years ago | (#33146294)

Hmm... that might solve that nasty global warming problem, too! In a roundabout way, I suppose... I say go for it!

How can it increase drag when there's no air? (1)

mark-t (151149) | more than 4 years ago | (#33145734)

I mean, I suppose there may be trace amounts of atmosphere up that high, but I can't imagine something even the size of a whole football field being able to effectively utilize the tiny amount of air that might be available to induce drag.

Re:How can it increase drag when there's no air? (2, Informative)

Sovetskysoyuz (1832938) | more than 4 years ago | (#33146164)

The equation for drag is force = 1/2 * speed^2 * density of atmosphere * area * drag coefficient. At orbital speeds, speed^2 is very large, so even a low density will produce significant drag. Also, the football-field-sized balloon has a very high cross-sectional area in relation to its mass, and even the mass of it plus the satellite, so the force produced will be still more capable of de-orbiting the satellite.

Re:How can it increase drag when there's no air? (1)

ceejayoz (567949) | more than 4 years ago | (#33146248)

As the ISS constantly loses altitude because of a slight atmospheric drag, it needs to be boosted to a higher altitude several times each year.

http://en.wikipedia.org/wiki/International_Space_Station [wikipedia.org]

Or easier ... (3, Interesting)

w0mprat (1317953) | more than 4 years ago | (#33145750)

Why not simply magnetize the dead satellite or include a small permanent magnet? This would create a magnetic sail. The magnetic field around the satellite would slowly trap plasma from the trace of gases and ions in earth orbit, as well as anything leaking from the sat itself. This would inflate the magnetic field lines and expand a kind of mini magnetosphere around the satellite. This would create drag against the earths magnetic field, and outer atmosphere.

Common permanent magnets can be much stronger than needed for this.

http://en.wikipedia.org/wiki/magnetic_sail [wikipedia.org]

Move it already (2, Funny)

Chimel31 (1859784) | more than 4 years ago | (#33145892)

Why don't we just do like we always do: Instead of cleaning up the place, move Earth to a less cluttered location in space?

Solve? (1)

Bobby Mahoney (1005759) | more than 4 years ago | (#33146088)

You keep on using that word. I do not think it means what you think it means.
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