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Boeing Proposes Using Gas Clouds To Bring Down Orbital Debris
cylonlover writes "Boeing has filed a patent application for a method of disposing of dead satellites and other debris orbiting the earth by hitting them with a puff of gas. The method, which is still at the conceptual stage, is designed to slow down satellites, forcing them to re-enter the atmosphere without sending up more space junk that itself will need disposing of. The idea is to send a small satellite into orbit containing a gas generator. This generator can be a tank of cryogenic gas, such as xenon or krypton, or a device designed to vaporize a heavy metal or some relatively heavy elements like fluorine, chlorine, bromine, or iodine. This gas would be released as a cloud in the same orbit as the debris, but traveling in the opposite direction."
Clever of them to patent this, since knock-off space-junk removal systems are in such high demand.
A space fart!
It's an apparently wholly new and unique method for doing something in the physical world. Why would it make them evil to patent that?
What about the increased amounts of persistent drag that these clouds will present to later satelite deployments? Spraying the gas does not mean it magically disappears after it has done its job. While inside the roche limit, the gas clouds will eventually (after thousands of years) fall back into the atmosphere, the cloud doesn't magically vanish after being sprayed, and widespread use of the technology would make it radically difficult to orbit new satelites.
If used outside the roche limit, the clouds become persistent!
I don't think there is much debris needing deorbited outside the roche, but with politicians and corporations at the helm, you can't be too careful.
The cloud wouldn't last very long, but long enough to hit the debris. By the time it hit, the gas would have expanded until it was almost a vacuum, so it wouldn't damage the debris. In fact, an astronaut caught in such a cloud probably wouldn't even notice it.
How do they propose to keep the non-junk from being de-orbited by the same gas? (I'm too lazy to read TFA.)
Physics.
Whenever a player quits EVE to go play WoW, the Average IQ of both games increase.
Please do correct me if I am wrong, but this reads like a patent application that contains a novel, concrete implementation of an idea that isn't necessarily obvious to one skilled in the art. That is what patents are supposed to protect, and I have to say I have no problem with that.
It's perhaps the first /. post in a long time that contains a patent that respects both the spirit and the letter of what a patent is supposed to be. It also sounds fairly ingenious and very interesting considering the possibilities, so props to Boeing.
This is such an obvious idea that it isn't right that it should be patentable. There are only a few ways of slowing an orbiting object down so that it de-orbits. The way nature does it is by putting gas in the way, called the atmosphere.
So basically we're claiming to patent inelastic collisions? So pretty much ANYTHING bringing something out of orbit by physically altering its orbit (which is almost always the result of an inelastic collision) will violate this claim. Broad much?
So basically we're claiming to patent a collision between two bodies traveling in opposing trajectories? .. seriously? Yeah, I was totally planning on knocking debris out of space by throwing rocks at it in the same direction it's moving!
So basically we're claiming to patent clouds between 100 and 400 km above Earth's surface? Because someone can avoid violating this by.. you know.. ignoring the debris between 100km and 400km. Right?
So basically we're claiming to patent clouds formed in different target zones? Is it possible to be any more vague?
So your projectile that will collide with the debris will fall back into the atmosphere. So would just about any other projectile-based solution. It'd be pretty damn hard to hit an orbiting object with another object with enough velocity to knock the orbiting object into the atmosphere and ricochet the projectile out of orbit in excess of escape velocity.
So basically we're claiming to patent spheres and hemispheres of gasses. Looks like a competitor will need to use rectangles, because this is the rounded-corners patent of gas clouds.
But seriously. C'mon.
Slowing debris down in the manner you have described is going to be very fuel intensive if you expect this disposable satellite to speed up to catch another piece of debris and slow down, rinse and repeat. I assume you aren't proposing disposable satellites for each piece of space debris.
That's what I was thinking.
Just releasing the gas in the path of the target satellite would slow down or speed up your vehicle enough to require course corrections. If you were to have enough gas on board to do two simultaneous releases on opposite sides of the vehicle you might be able to mitigate this.
But simply getting to the proper place for EACH of the thousands of sats and space junk targets would take a lot of maneuvering.
This seems overly complex and subtle. Its main advantage seems to be that it leaves no debris in orbit.
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That's the equivalent of having one trash truck for every house and then just driving it into the landfill instead of dumping it. Good plan.
This reminds me of another method using light instead of gas, which was described at a recent space conference. The idea was to pulse laser light toward the west (since most space debris is traveling predominantly eastward), and over time the photons alone could provide enough delta-v to nudge things out of orbit more quickly. For the big stuff they have other plans in mind, such as electrostatic tethers and micro-rockets. But for little stuff, the light pulse would be a cost-effective "shotgun" approach to deal with the cloud of crap that's too small to track.
Sorry I can't find a link at the moment. I saw it a few months ago on YouTube from either NewSpace or SpaceUp, or ISDC or one of the other conferences in the last year or two.
XML is like violence. If it doesn't solve your problem, you're not using enough of it. --AC
Found an article referencing the water spray idea.
Boeing:
LegendMUD
Actually, probably not. That's the beauty of this. Shooting gas at a satellite might cause some orbit degradation, but it'd be tough to do something really nasty to it. This only works against small pieces of debris, much smaller than any satellite. Which has, incidentally, always been the most worrying aspect of orbital debris.
Actually, for those sats that share orbits, this would be a problem, which is why they use a gas that would disperse in short order.
Presumably any sats that were not targets, but still close enough to the gas cloud, would eventually need a slight nudge to correct their orbit, but then that kind of orbit correction happens occasionally anyway. (One definition of a dead satellite is one that has no maneuvering fuel left to do station keeping.). So if your satellite is still operational it probably would not be affected by the gas.
This ability to affect a large area actually works in your favor. You can deorbit entire debris fields with this technique.
However, some space junk deorbited this way could drift into conflict with low earth orbit satellites, like weather sats and GPS sats. So some planning would be necessary. And since the gas is designed to ever so slowly deorbit the junk, your ability to control this is minimal at best, because it could take years.
I'm glad Boeing patented this because they actually have the ability to deliver, whereas some patent troll could just use it to extract money.
I'd be happier if they just built one and and demonstrated it, and then offered it for sale. Even happier if they just declared the patent free to the world.
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You enter higher or lower orbits by speeding up or slowing down. If you fire at right angles to your direction of travel you increase your velocity and end up in non-circular orbits.
Clearly the customers here are Governments.
One of the first orbits to be cleared would probably be around the ISS.
John Campbell of Iridium spoke at a June 2007 forum discussing the difficulty of handling all the notifications they were getting regarding close approaches, which numbered 400 per week (for approaches within 5 km) for the entire Iridium constellation. He estimated the risk of collision per conjunction as one in 50 million. Yet in 2009, less than two years after he made his prediction, his company lost Iridium 33 to a collision.
To date, there have been eight known high-speed collisions in all, most of which were only noticed well after the fact.
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Here's a quick summary of the procedure you're talking about: http://www.technologyreview.com/view/423302/nasa-studies-laser-for-removing-space-junk/
Initially, they were thinking of ablating the surface of the junk with the laser, but turns out you need a hell of a lot of power to do that, so it wouldn't be very economical. More recent calculations suggest exposure to a ~5kW laser might be enough to decay the orbit enough to bring it back into the atmosphere where it'll burn up, and they estimate that a device such as this, big enough to handle 5-10 objects a day, could be put together for a few million dollars.
Not only that, but you are sending up a unit to bring down a piece of space debris.
So are you launching an object on top of a rocket into space. Then you have to blow the aerodynamic covers off while in orbit.
At that point the craft can latch on to one of the 2 covers now in orbit and bring it back down.
Why is it so hard to only have politicians for a few years, then have them go away?
No, this is not a tragedy of the commons, this is yet another example of externalising expenses - same as dumping toxic shit into a river or burning coal to generate electricity.
Unless there's a bill to pay or laws to prohibit it, you can get away with pretending that the expense of managing and disposing of your waste doesn't exist (and, magically, for YOU it doesn't exist).
You get the benefit of your waste-producing activity, but everyone else has to pay for it.
The "Tragedy of the Commons" is a popular meme for libertarian types who want everything to be owned (preferably by them so they can extract monopoly rents from the previously public resource)...and because TTotC is a such a popular and self-serving meme they are selectively blind to the thousands upon thousands of examples of privately-owned resources which are completely trashed because their only value to their owner is in the maximum extraction of profit in the shortest time (strip mining, toxic or radioactive tailings dams, clear-fell logging for example) or as a dumping ground for waste from some other activity.
But a commons doesn't have to be owned to be managed successfully, it just has to be regulated - so that, e.g, one private company can't take a giant dump in everyone else's favourite picnic spot. Regulation, however, is anathema to libertarian types. They feel that if they want to lay a turd on someone else's picnic blanket, either directly or a few miles upstream, then they should be able to do so - "Freedom!"