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Space Sails Could Bring Used Rockets Back To Earth
GordonCopestake writes "An article from New Scientist proposes that all new spacecraft have sails attached to bring them back to earth — a measure that would reduce the amount of garbage in space. From the article: 'The risk to spacecraft from a collision with space debris could be reduced by equipping launchers with a gossamer-thin "sail." The idea is to deploy the sail after the rocket has released its payload to amplify the drag of the last vestiges of the atmosphere, and so force the rocket out of orbit.'"
Wired has a related story about the risks faced by the space shuttles as they share orbits with tons of drifting space debris. "... in the 54 missions from STS-50 through STS-114, space junk and meteoroids hit shuttle windows 1,634 times necessitating 92 window replacements. In addition, the shuttle's radiator was hit 317 times, actually causing holes in the radiator's facesheet 53 times."
We should not stop producing CO2. We are gonna need the heat when all the space junk blocks the sun. Why do humans have a need to choke on their own waste? Are we really a bacteria or something?
This might be helpful for rockets launched in 4 or 5 years (Which I think is a very generous estimate on how long something like this would take to be adopted even close to universally.) it doesn't address the issue of all the stuff already up there. How long will the majority of the debris in orbit remain? How effective are these sails when they themselves are punctured by debris? It's a great plan for keeping things from getting worse, but as I understand, a lot of things up there that are in danger of causing damage will be up for quite some time.
When we've got countries blowing up satellites in orbit, that's far worse than a big booster plodding along in a decaying orbit.
I swear to God...I swear to God! That is NOT how you treat your human!
Those numbers are frigging huge compared to what I thought. 300 measurable hits per mission is crazy. And it will only get worse. I don't think sails are the solution. We need a way to clean it up. (While i liked PlanetES I don't think doing it by hand is very viable)
The universe is mocking us for not thinking ahead. Again.
And our reaction? "Let's make those pieces bigger!"
this might be where Private Enterprise wants to step forward and work on getting a space ship to approach a used up sat, and attack a sail to it to force it down the gravity well. With small control units on the sail, this could be really useful. That same tech would be needed for remote servicing of sats anyway, if private enterprise wants to take that on. As to who would pay, well, I would guess that whoever owns the sat would find it cheaper to pay 5-10 million to de-orbit a sat than deal with lawsuits. For the small to medium size, well that will require a totally different approach.
I prefer the "u" in honour as it seems to be missing these days.
Well, with the kind of weapons tech being developed (electric eye with lasers?), it shouldn't be a big deal burning down these debris. The problem would be allowing (or acknowledging that *anyone* has) that kinda weaponry up there.
Real men read Slashdot articles at -1, bottom up.
I wonder if we could operate a remote-controlled Mass Catcher? The one designed for the 1975 Stanford Summer Study would do if you left off the intake grid of cables. It would be a rotating Kevlar cone. Centrifugal force would hold loose regolith in place, which would act to absorb the impact of the intercepted debris. The same rotation would also act as artificial gravity to prevent the escape of secondary splash debris. Using a pellet launcher as a thruster would be safe, since the pellets would be traveling at far above Earth escape velocity.
Instead of sending it back to earth, why not just keep it out there, but collect it all to one central location? We paid once already to launch it out there, and we know we want increase our space presence, so why not have a junkyard where you can go get stuff to recycle? Or, crash it into the moon and build your moon base near it, then you can keep adding to and utilizing it.
Now that you mention it... Maybe we should try launching politicians up there to collect the debris. Or bankers.
Can we build something cheap enough to launch them all?
You're going to get a hole in your radiator.
You're going to get hit in the window 30 times.
Two windows will need to be replaced.
"For the final stage of an Ariane 5 launcher, the conical sail would need to have an area of about 350 square metres and be supported by an inflatable mast 12 metres long."
And the expected time to reentry is 25 years.
Good luck on keeping something inflated in space for 25 years. And that's not even considering the probability that the the mast, and the much higher probability that the large sail, will be hit by orbiting debris during that time and torn to shreds
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
These are fucking tasteless and annoying. Post a legitimate criticism if you must (and there are plenty; just read /. for five minutes), but please stop being a fucking 13 year old.
(and yes, I know I'm feeding the trolls)
If you blow up an old booster ... or satellite ... you only make the space junk problem worse. Instead of 1 large lump of junk that is easy to track and (with luck) avoid, you end up with thousands of smaller lumps, each of which would damage or destroy a satellite.
So the same species that has brought us to the brink of destruction by fouling its own nest has so polluted the near-space environment that it is no longer safe to send humans up there. What a shock! When's the last time you looked up to see if you could see anything "up there?" Like a star or a planet or, shudder, a neighboring galaxy? Relatively few people do that anymore because of all of the f'ing lights we think are so important and make us so secure!
Not with a bang but a whimper.
Here is my idea for making an extra light solar sail:
http://kim.oyhus.no/Solar_sail.html
Kim0
It's rather like taking a stroll down Main St. in one of those western cowboy movies.
Anyone know how powerful a big electro magnet would have to be to suck debris within say... a mile, towards it?
You could vent water vapor in the path of denser groupings of debris. This would allow you to sap kinetic energy from clouds of debris without incredibly fancy or expensive lasers. Still, getting large volumes of water up into space is itself a costly endeavor and might only be cost effective in bringing down denser debris clouds or groupings. Add that to the fact that water vapor will disperse and descend rather quickly and this might only be viable as a way to clean up right after a debris creating event occurs.
Aerogels are a possible means of collecting and de-orbiting debris. Unlike water vapor, these materials would not disperse as rapidly and could be used to sweep out regions of debris by providing enough resistance to slow them down and drop them out of orbit. The problem here is that the materials with the requsite properties don't nescessarily exist yet- if you consider mass production and low cost to be requisite properties. Ideally the aerogel would be one that could be produced on-site; meaning it could be carried in a dense component form and sprayed out into space. Carrying fully formed areogel into space for the purpose of debris collection would prove impractical due to the large volumes required- though the low mass required makes the idea of on-site production appealing.
There are several promising aerogels - particularly alumina based compounds - that are already used for capturing high velocity particles. The trick would be creating a mechanism capable of generating them in orbit.
Space sails? That's so low tech.
It's obvious we need deflector dishes and shields.
Star Trek has taught us that much!
Down With Slashdot BETA!!! I've been around the corner and seen the oliphant; you can only abuse me from your perspecti
The problem with space travel won't be the engines or how to recycle the used food, it'll be all the rocks constantly beating on the hull.
No sig today...
Any ban that is worth their salts would have a description wanted, a means to verify, and a means to punish those that break that. BUT, that is impossible to do. Take the case of North Korea. Clinton got NK to agree to not do Nukes. It was absolutely prohibited from doing so. Ok. BUT W came into office and started calling NK names. Instantly, it is found that NK has been doing all the steps that are useful for civilian as well as military while pure civilian steps are missing. IOW, they met the letter of the law, and then looked for an out. W then got an agreement out of NK to shutdown their reactor and give up their pursuit of bombs. Ok, no problem other than the fact that NK has prevented inspectors to go where we KNOW that military work WAS going on. AND again NK pursues OTHER banned pursuits, namely a delivery system. Suddenly, NK is announcing that they will re-pursue the bomb since we want to inspect an obvious missile system.
Now, how does this relate to China? Well, Clinton gave MFN to China back in mid 90's. In return, China was to free their money against the dollar as well as drop their trade barriers in early 2002. Did they? Nope. W did nothing to push, while China racked up monster theft of businesses. Now, we are extremely weak. China refuses to do these things even though EU is now insisting on it. Remains to be seen what will happen there.
How does that relate to China's military pursuit? China pushed this banned and trying to get America as well as NATO to lower our military, all the while spying on production of weapons. They are building up 2-4 new nuclear subs a year (1-2 boomers and 1-2 attacks). Of course, they just moved that production into a "hidden underground base" and are trying to prevent the west from seeing the subs from leaving. That was the recent harassment against a US intel ship that was JUST beyond the 200 mile marker. They have been quietly pursuing a quasi-civilian space agency that is ran by the military. No problem, though it is not that open. They have on the board a space station that will be similar to ISS. BUT recently they announced a NEW space station(s) that will be pure military ran. No advantage to it for monitering. None what so ever. The reason is that recon Sats will do a much better job since they can be moved rather quickly compared to manned space station. So what purpose could it have? Ease of adding space weapons.
Space ban is worthless because the one that pushes it has no intention to doing it. And we have no easy way to verify it. More so when said country is still in obvious military cold war.
I prefer the "u" in honour as it seems to be missing these days.
I think that any mass in orbit is far more valuable there than back on earth. It still has all the energy the owner has paid for by launching it in the first place, and at ~$1000 per kg in LEO that is nothing to sneeze at. I think the solar sails should be used to cart the stuff into a higher orbit where the parts can be stored with less effort.
The problem is that whatever we sent up is not built for reusability it would seem. Without a decent plan to produce something from space junk I guess nobody is going to worry about where the hardware in orbit goes beyond its eol, it has paid for the launch costs already why worry about much costlier manufacturing in orbit. Then it is also safer to just drop the stuff. This proposal is more of the same shortsighted thinking however. We will continuously put stuff into orbit, why let it decay back to earth if there could be a continuous reuse of material in orbit? Something goes up nothing comes down!
The space junk problem could finally lead to better planning for the future. Somebody could come up with an in orbit manufacturing and launch facility which buys the energy + material value of your satellite/booster. Its main bussiness would be in orbit manfacturing and launch of hardware with a certain orbit.
I would venture a guess and say that we already have the technology to make this work today. So it is time to check whether this could become a viable business model.
Je me souviens.
Pointy sticks to spear the space trash.
Contribute to civilization: ari.aynrand.org/donate
use the sails to move them into higher designated parking orbits so the materials can later be used up there when we need to start assembling craft in space... it costs an enormous amount to put mass up there, why waste the energy invested?
Donald 'Duck' Dunn: We had a band powerful enough to turn goat piss into gasoline.
Issue licenses to commercial space flight providers. Their spacecraft would be fitted with big-ass laser canons. Rich folks would fork out a few million for the privilege of bagging some space debris.
Each flight would have "Space Hunting Guides & Skinners," grizzled, experienced former government astronauts. The skinner would ensure that there was no smaller junk left over after the kill. It would be burned up in the nightly campfire with a yet-to-be-determined technology.
The guide would say cool stuff, like, "Now you've got to be careful when stalking a Sputnik . . they are crafty little bastards!"
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
Which is why bigelow's BA-330 is interesting. About a foot of material as well as sealing that ABSORBS the item, rather than trying to reflect it. For distance travel, do the smart thing and put that in a metal can.
I prefer the "u" in honour as it seems to be missing these days.
And it involves sending a lot of baseball players to space, with steady supplies of baseball bats.
Why not take this further. Shoot up rockets with big sails attached for the sole purpose of collecting space debris. put them in an orbit then deploy their sails or parachutes so they will catch a swath of debris. if the rocket is traveling slightly faster than the debris the sail wont be punctured and it will fill up before losing its velocity and then falling out of orbit.
A fool throws a stone into a well and a thousand sages can not remove it.
Compared to the TARP funds, rocketing those assholes into orbit would be cheap.
Power does not corrupt - power attracts the corrupt.
http://www.tethers.com/TT.html
I saw Robert L Forward talk about this at a con years ago.
Instead of atmospheric drag a conductive tether moving through the Earth's magnetic current generates a current and radiates the heat from tether resistance. The dissipated energy will eventually bring the satellite down. The technique has been developed by Tethers Unlimited and the late Dr. Robert Forward
http://www.tethers.com/TT.html
Stop worrying about the risks of nuclear power and start worrying about the risks of not using nuclear power.