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DARPA Aims To Reuse Space Junk
CowboyRobot writes "Space junk has increased to the point where pieces of it are colliding and breaking into smaller pieces. The problem is now so bad that NASA has had to modify the design of satellites to protect them from flying debris. The Defense Advanced Research Projects Agency (DARPA) wants to turn disabled satellites and their components, including antennas and solar arrays, into functioning systems. They are hosting a conference on June 26 to explore how to build 'refurbished' satellites from already-orbiting material for less than what it would cost to build them from scratch and launch them from the surface of the Earth."
Flying magnets?
It costs several dollars a gram to get it up there, it only makes sense to try to recoup some value. Reusing it does not nearly have the security concerns of forcing it down and burning it up.
"She's a scientist and a lesbian. She's not going to let it slide." Orphan Black
on a bright spring day in 2020:
Dammit. I think the Chinese just refurbished our operating commsats and used the parts in one of their early warning satellites.
Seriously. If you can do this with abandoned satellites, can you do it with not-quite abandoned ones? The only difference between junking a car at the junkyard and stripping a car on the street (besides location) is the fact that someone still owns the car on the street.
We're gonna wind up with satellites with no radio, no trim, and up on cinderblocks.
Welcome to the Panopticon. Used to be a prison, now it's your home.
Start with mining orbital junk before heading out to the asteroids. Must be plenty of useful metals and minerals to recover via automatic factories.
UNIX/Linux Consulting
This is a really good idea, considering the fuel cost to get something up into orbit, plus the nonzero risk of the launch itself. Heck, if we can start with refurbishing 'orbital junk', we're getting into orbital manufacturing. Mix in an odd asteroid for raw materials, and we might actually get off this rock!
"Dude, Where's My Satellite?"
Because if they do, we will have backdoors into their spy satellites. Plugging a found USB drive you find in your company parking lot into your computer is an iffy proposition, plugging something into your satellite is just foolhardy. Best case, it's a bomb, worst case it's a monitoring device.
All ideas^H^H^H^H^Hprocesses in this post are Patent Pending. (as well as the process of patenting all postings)
Planetes
Operation Guillotine is in effect.
Modular refueling would be useful. Sometimes the only thing that dictates the life of a geo sat is the station keeping fuel supply. When it's about to run out, a geo sat is put into a graveyard orbit, where it's not supposed to hurt anything. If you could send up a small fuel supply ship that could pull a few sats from the graveyard, put the good parts together with perhaps new batteries and gyroscopes, you could get a much bigger satellite than if you had to launch a brand new one.
If you built your satellites with a fuel/engine section that had the gyros and anything that normally wears out, a solar panel section, and payload sections, so that you could pull them apart and put them back together Lego style, this idea might be workable.
All ideas^H^H^H^H^Hprocesses in this post are Patent Pending. (as well as the process of patenting all postings)
X-37B?
What do you reckon?
Stick Men
Put an orbiter into an orbit that brings it into contact with a more massive dead satellite. Grab it. And use a magnetic servo or some other tool to hurl it downwards at Earth....and you go up. Maybe more efficient than spraying out mass using a booster?
Like the economics weren't blindingly obvious enough when they launched the effing stuff in the first place?
Salvage 1 - the junkyard astronautics http://www.imdb.com/title/tt0079847/
Paul: Father... father, the sleeper has awakened! - Dune
Also, if there is technology developed to gather fragments in orbit, it should be feasible to use it to gather zodiacal light comet fragments -- appropriately scaled.
Seastead this.
. . . for most platforms is either failed/failing batteries, or failed maneuvering systems (low fuel). To repurpose that, you've got to get TO the platform, and re-fuel, repair. We just mothballed our shuttle fleet.
There's the new spaceplane thing they've got, that's capable of rendezvouz, and changing orbits, but it's unmanned.
So, I don't see how they can pull-off a refuel/repair job, totally unmanned like that. STS succeeded with Hubble, what, 3? 4 times?
The problem is simple, and was predicted long ago: In the Kessler Syndrome we have a cascading effect where every collision begets more collisions which create more, smaller bullets which impact... you see the cycle yet?
We really, desperately need to do two things:
1) Find a cheap way to collect the garbage.
2) Find a cheap way to get to space.
While rockets are nice and all, we really need something like a Space Elevator or a ground-based Launch Loop in order to commoditize space travel sufficiently that things like space-junk shielding can become the norm.
Also, why is all this junk going in all directions? It would seem appropriate to coordinate the launches and orbits so that there are "tubes" of orbit where everything goes in more or less the same direction so that collisions don't occur.
Aircraft do this - planes going east fly at odd elevations (11,000 feet, 13,000 feet, etc) and west at even elevations. (10,000, 12,000, etc) Why can't satellites?
I have no problem with your religion until you decide it's reason to deprive others of the truth.
The EDDE system at http://www.star-tech-inc.com/ seems to be practical.
I wouldn't necessarily require that you be able to refurbish for less than it'd cost to build+launch new.
Instead, you should set the bar at "less than it would cost to (build+launch a new satellite)+(cost to remove debris used in refurbishing)".
If it costs $4 mil. for a new satellite, and $2 mil. to cleanup one satellite's worth of debris, but you can instead have a solution that uses that debris to create a satellite in orbit at a cost of $5 mil. then you've saved $1 mil. even though you did it at a costs greater than building a new satellite.
I have said this atleast for the last 5 years, even before they retired the shuttle...I said, send it up there, and leave it up there, so instead of just rusting down here, it can be reused for its parts, and maybe get even more stuff built out there, then it would be with just the satellites.
The Slylandro tried making probes that reused the materials around them... it didn't work too well.
outside of sending Newt up in a space suit with duct tape and a 9-ton oxygen bottle, since he's a spacehead and has lots of free time now, we really need to concentrate on gathering the krep into one place, and putting a blinking electronic "X" on the spot. this is doable, and since everybody is responsible, everybody needs to chip into the pot for a "free" project.
basically a robot dogcatcher with a very fine "net" is needed to close and capture the drifting trash. as to whether any of it is useable... good opportunity for technocrooks. send 'em up in an old Buick with suits, so they have the back seat as a workbench, and let 'em paw through the junkpile. if they can find a way to fly home in a space jitney, they're free.
if this is supposed to be a new economy, how come they still want my old fashioned money?
.
One android satellite development program, $3.8 trillion.
One heavy lift rocket to lift that satellite into orbit $3.7 billion.
One load of oxidizer/fuel mixture lifted into space to catch one low earth orbiting satellite, $5 million.
One dead US satellite in low earth orbit, return value $0.
One live Chinese spy satellite in low earth orbit, return value, priceless!
Funny how the same set of tools used to dismantle old broken US satellites is also approximately the same set of tools needed to dismantle and examine the Chinese, N Korean, or Iranian satellites, isn't it? Dismantling old broken US satellites will never be cost effective, but having knowledge of say Soviet and Chinese spy satellite technology is no doubt absolutely priceless. Of course I must be wrong, because the fine article never said anything about 'other peoples' satellites.
http://hardware.slashdot.org/story/11/10/22/0420236/darpa-proposes-ripping-up-dead-satellites-to-make-new-ones ....for earlier comments and discussion
~doooooo, do do de doo do do dooooooooo~
Because if they do, we will have backdoors into their spy satellites. Plugging a found USB drive you find in your company parking lot into your computer is an iffy proposition, plugging something into your satellite is just foolhardy. Best case, it's a bomb, worst case it's a monitoring device.
Ahhhh so THATS why the USA 'let' the Iranians capture that spy drone!!! It all makes sense now.
In the free world the media isn't government run; the government is media run.
Hadn't thought of it in that context, but yes, the drone could have been intentionally crashed to detect holes in Iranian defenses. A flying Trojan Horse.
Most likely, the software wiped itself when the thing crashed, but it's not impossible that the drone had redundant copies of the flight software. Except one "copy" has the buggy or Trojan software and on crashing, the bogus version was moved into the flight areas. Or, there was a thermite charge above the brain, that slagged it down.
All ideas^H^H^H^H^Hprocesses in this post are Patent Pending. (as well as the process of patenting all postings)
Your comment makes the common mistake of Earthlings, that distance equates to cost. On Earth it does, because transport involves either rolling friction, air drag, or wave drag, depending on transportation method. In space none of these apply, so the cost of transportation is related to velocity change, and not distance.
Dead synchronous communications satellites are spread out in a 263,000 km ring around the Equator, but they are all moving at nearly the same velocity, the amount to match the Earth's rotation and make them synchronous, so gathering them up won't take much velocity change. Also, new electric thrusters are ten times as efficient as old chemical thrusters, and make a wider range of missions possible than before.
Some of the dead comsats are still functional, and just ran out of station-keeping propellant to keep them in a fixed location. The point of synchronous satellites is all the ground antennas don't have to move, cause the satellites stay in one place in the sky. Fixing those satellites just involves clamping on a new fuel tank and thruster pack, and you are good to go.
More advanced repairs would involve remote controlled robots, likely, to replace other items like worn out or broken solar arrays. Fixing internal failures, like the amplifiers for the downlink transmitters would need a hangar and humans given our current robot capability, so that level of repair will need to wait for lower cost humans in orbit. At the least, we can gather the space junk into controlled orbits so it doesn't breed more space junk by collisions.
Only the simplistic single noodle stationary space elevator (devised in 1895 for gosh sake) needs Unobtainium for building materials. For a more practical design see this page in a space engineering textbook I have been writing (along with anyone else who contributes, but mostly me so far):
http://en.wikibooks.org/wiki/Space_Transport_and_Engineering_Methods/Space_Elevator
The short version is that both rockets and space elevators get exponentially more massive with increased velocity. Therefore if you split the velocity to get to Earth orbit between the two methods, they *both* are much less massive than either by themselves. Thus a Skyhook type elevator that provides 2.4 km/s has a mass ratio of 16 times the arriving vehicle mass using existing carbon fiber and reasonable design margins (2.8:1 on the bare cable strength).
The rocket coming from the ground performs the remaining 6.6 km/s ideal velocity, and has a 13% payload fraction assuming LOX/H2 propellant. The ideal velocity is 27% lower than an unaided Single-Stage-to-Orbit rocket needs to do, which accounts for the higher payload. The Skyhook has a landing platform at the tip which the rocket does a vertical landing on. When returning to Earth, the rocket merely drops off the landing platform, and now has to dissipate slightly less than half the kinetic energy as returning from full orbit, so the heat shield problem is that much easier.