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Grave-robbing DARPA satellite to form new orbiters from dead equipment (extremetech.com)
25 points by mrsebastian on Oct 21, 2011 | hide | past | favorite | 18 comments



How does satellite tracking work? Does a country like Russia or US track every single one of its satellite and each others' satellites?

Imagine if Russia or China just launched a satellite that showed the capability to grab and take apart & examine American satellites while in orbit.

They can clearly destroy them but having the ability to examine them would be a bit of a game-changer, since it is assumed satellite with latest super-secret techs are safe after the launch?

Do some fancy satellites have proximity sensors and self-destruct mechanisms...?

I know Russians have built one of their manned spy sats ( Almaz?) with an anti-aircraft gun designed to be used if American satellites would approach it.


>Do some fancy satellites have proximity sensors and self-destruct mechanisms.

If the opposition had just spent $XXXBn on a reusable space shuttle to retrieve satellites and you were a paranoid cold war enemy wouldn't you?


Would. Except for the ones I already launched...


I think this sounds like a lot of fun if it works. Might provide consultancy jobs for elderly space scientists as well - they would remember what was really in the circuits, and all about those quick undocumented fixes to the software....


I have always thought that ground based lasers were the best solution to the kessler syndrome. I wonder if the benefits of this system would make it more cost-effective.


What would you do with the lasers? Heat 'em evenly so that they vapourise smoothly instead of falling apart and forming lots of little bits?


http://en.wikipedia.org/wiki/Laser_broom

In short, you use it to heat one side if the debris, causing it to ablate, resulting in thrust that knocks it out of orbit.


Since satellites aren't designed with that sort of ablation effect in mind, I think hugh3's point that it would fall apart as various connecting bits burned through early would be much more likely.


The article states that it's designed to be used for bits from 1 to 10 cm, which mostly means stuff that has already fallen apart.


It sounds all very intriguing from a technical point of view, but how much less would it cost than putting up a whole new satellite into orbit?


The most expensive part of the whole process is getting stuff into orbit. The main reason satellites have to be super-reliable is that even getting such levels of reliability is cheaper than sending up a replacement.


Maybe it's cheaper to build a new one and send it into orbit. I guess the purpose is to avoid creating more space debris, not to cut production costs.


So apart from the tricky business of grabbing a bit of space junk going past you at Mach33 and changing it's delta-V so you can grab it and attach it to your satelite.

And the tricky business of dismantling a satelite and somehow re-wiring a dead 1970s TV broadcast sat into being a new earth resources bird.

It's then going to presumably reach down into the Silicon lattice structure of the panels and remove all the defects that 10years in space has introduced.

- You know all those secret DARPA/CIA projects on mind control drugs in the 60s the conspiracy nuts talk about? I think we have found their stockpile - and I suspect they might have a leak!


So apart from the tricky business of grabbing a bit of space junk going past you at Mach33 and changing it's delta-V so you can grab it and attach it to your satelite

It'll be in (essentially) the same orbit, so it'll be drifting past the other satellites nice and slowly.

And the tricky business of dismantling a satelite and somehow re-wiring a dead 1970s TV broadcast sat into being a new earth resources bird

This is tricky. But mostly they just seem to be salvaging the dish antennas, which should be pretty interchangeable.

It's then going to presumably reach down into the Silicon lattice structure of the panels and remove all the defects that 10years in space has introduced.

They don't seem to be salvaging solar panels.


It'll be in (essentially) the same orbit, so it'll be drifting past the other satellites nice and slowly.

What are the range of velocities of objects in graveyard orbit? I wasn't able to find these numbers directly on a quick google search


The orbit you are in is directly dependent on your velocity. So if your orbit is similar to another objects, you'll be going at a similar velocity as well.

Put another way, if you are in the same orbit as another object, your velocity must be the same.

This illustrates itself in space docking procedures. If two objects are in the same orbit, one thrusting towards another in the direction of the orbit puts the first at a higher orbit and it'll rise with respect to second object. The converse holds true; thrust against the orbit and you'll fall with respect to the other object.

Thus, to dock, you have both crafts at slightly different orbits and the lower orbit will slowly gain on the higher orbit. In this way, one can control how fast the approach is. This will be how the satellite approaches debris most likely.


Andy Griffith, with a little help from Isaac Asimov, has already solved this problem.

http://en.wikipedia.org/wiki/Salvage_1


I smell a disaster in the making. What if it goes into the wrong orbit? It could cut into the ISS! Also, wouldn't a giant magnet make more sense?




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