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EPFL's CleanSpace One Satellite Will "Eat" Space Junk
Zothecula writes: Working with Geneva's University of Applied Science and Signal Processing 5 Laboratory, Swiss research institute EPFL has announced details of a plan to capture its tiny SwissCube satellites by using a new spacecraft outfitted with a conical net. Called "CleanSpace One" the team hopes that their "Pac-Man" solution will capture the old satellite. Gizmag reports: "...SwissCube's spinning action will make it more difficult to image, as its surfaces will alternately be brilliantly sunlit or hidden in shadow. That's why CleanSpace One's computer vision system will be running algorithms that account for variables such as the angle of the sun, the dimensions of the target, the speed at which that target is moving, and the rate at which CleanSpace One itself is spinning. High dynamic range cameras will also allow it to simultaneously expose for both bright and dark surfaces."
The Last Starfighter
I always figured the hard part was detecting/locating debris, more than bumping it towards reentry or escape velocity.
I also always figured Planetes was going to be unmanned machines in practice.
/obligatory
Basically, this satellite need to joint the orbit and velocity of it's target. It seem a lot of energy to remove "one" debris. If something need to be done, wouldn't a freaking big net or something be better?
Elok
This has been a growing problem that no one has made a realistic attempt to solve. Glad someone has finally started working on it.
This isn't a realistic solution... About all we can conceivably do right now is go snatch larger hardware assemblies and either bring them down or put them into parking orbits out of the way. Getting the real dangerous stuff, moving at huge relative velocities is like trying to catch bullets using your fingers. All you will do is put a whole though your fingers and likely just create more junk in the process.
We would have better luck if we would vaporize this stuff from the ground or push it into decaying orbits using lasers or something. Trying to go up and catch it using a net is not going to work unless you can get the relative velocities nearly identical and who has the time and energy for that?
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
Let me guess, it tries to eat the USS Constellation?
EPFL stands for Ecole Polytechnique Fédérale de Lausanne (Lausanne Federal Polytechnic School). It is not a "research institute" but one of the two (with ETH Zürich) swiss federal engineering schools, and very renowned at that. Lots of good research labs there, too, just like at MIT or Caltech, but that doesn't make them "research institutes" neither.
Its mission may not be pure research, but it implicitly self-identifies as a research institute (among other things) on its website:
With more than 300 laboratories and research groups on campus, EPFL is one of the Europe's most innovative and productive technology institutes. At EPFL the emphasis is on both theoretical and applied research.
If it weren't for deadlines, nothing would be late.
The world is a big place. Hard to know everything. America is a big country, hard enough to know everything that goes on here. The population of the entire country of Switzerland is 1/3rd of Southern California and only 1/4 the size.
Southern CA is 1/3 of California and doesn't include Stanford, Silicon Valley and all of the high tech research facilities there. And not all the research facilities in the US are in California Most states have high tech hubs.
http://www.wolframalpha.com/in...
http://www.wolframalpha.com/in...
And here are their research centers which are analogous to institutes.
If it weren't for deadlines, nothing would be late.
I would think that metallic satellites would be good targets for RADAR VS. optical tracking.
"A 'person' is smart. 'People' are dumb, panicky animals and you know that."
I'm no rocket scientist but this is nuts. We are going to launch some satellite, have it capture another one, then deorbit both of them? What a waste! A waste of energy and technology to launch such hardware just to throw it away. Not to mention that orbiting broken satellites might have some useful components we might consider trying to recycle. A big dish antenna is heavy, but could conceivably be reused and save launch weight on the next satellite.
These larger pieces of space junk are easy to track, few in number, and thus are not that dangerous. What we really need is a solution that allows us to start clearing out the smaller pieces of junk. Maybe by just nudging them around until they are in decaying orbits, or vaporizing them using lasers. If we are going to talk pie in the sky, let's do something more useful...(and perhaps more likely to be successful.)
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
It's also a solution that requires a lot of fuel
If they could find a way to catch and crunch up the debris. They could eventually make a large light show by sending the debris into reentry over a populated city. Auction the light shows off....
We need to start by grabbing and deorbiting the largest debris pieces, before they spall off smaller pieces. Space junk gets harder to economically intercept with decreasing size, but solar pressure will eventually sweep out the smallest stuff.
Figure out a cheap way to make a low-density material aerogel in space. Make a large quantity of it as a single mass (doesn't have to be a cube - could be a sphere) and put it into an eccentric orbit which intersects some of the orbits with the most junk. The stuff is good at catching small high-velocity particles without fragmenting. The high surface area to mass ratio means its orbit will decay a lot quicker than regular junk. So put it into a (relatively) high orbit where it'll collect junk for a few years, before aerodynamic drag degrades its orbit and it (and the junk it's caught) burns up on re-entry.
Hopefully this thing is just a proof of concept, any such system should be able to capture multiple pieces of debris whereas this this thing seems physically limited to capturing a single piece of debris and deorbiting. That simply is impractical with over 19k pieces of debris over 3.9 inches in size to launch a satellite for each and every one. Even if each satellite had the fuel and storage to capture 100 pieces of debris that would be around 190 satellites. A better concept might be to have a couple dozen LARGE satellites (Delta IV or Falcon Heavy) in different orbits each with a dozen or so retrieval craft that go out and collect a few pieces of debris and then return to the mother satellite and drop off their debris and refuel for another trip. After the mother satellite is either out of fuel or full of debris it deorbits itself along with its retrieval craft.
It's all dangerous stuff and there is value in cleaning up the easy to get to stuff.
With all the deltaV needed to get around there is no way to get all of it with one device anyway, so getting everything was never the plan.
One thing I was reading about this morning was all the solidified large drops of liquid sodium coolant from decomissioned satellite reactors - not so hard to get to and clean up but dangerous if you get in their way going at a very different velocity. A lot of those are gathered relatively close to each other, so you could get a bunch of junk without having to move around much.
Only if you move around a lot. Getting junk in very similar orbits still have value, and there is a lot of that due to some items ending up in many pieces. Trying to get it all is just a paper exercise in demonstrating to people how much deltaV is needed to treat a spacecraft like an aircraft.
"Vaporizing" satellites doesn't really help you. All you've done is split one big satellite into a whole bunch of tiny satellites, each of which is still moving at orbital velocity (thanks, conservation of momentum..). Except now you have a dispersed debris field moving at orbital velocity instead of a single satellite.