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Indian Robot Will Capture Space Debris
CowboyRobot writes "India is set to launch the 'Space Robot', which, controlled from Earth, will capture damaged satellites and space debris. This seems a less ambitious, and more immediately practical venture than the current Mars missions."
Somehow I doubt that the US didn't have the robotic technology... I imagine a seasons worth of battlebots constructors could handle this task.
In fact, that confirms it. I think any of the spinner bots would work...
Sig under construction since 1998.
The 'Space Robot' (SR), with an in-built 'RUDAC' communication signal processor, will be used to capture damaged satellites and space debris from crashing to Earth, CSRDC-CSRL and ISRDO Director Dr M Sreedhar Dayal told UNI.
Putting aside the poor translation, it's clear that the article's writer doesn't have much of a scientific background. Unless you're talking about a mass comparable to the Compton Gamma Ray Observatory or perhaps the Hubble, there's not much need to prevent debris from "crashing into the earth". 100,000 feet of atmosphere does a fine job by itself, and puts on a great light show to boot.
The obvious benefit of this space scoop is to clear NEO of the sort of debris that occasionally causes the ISS and the Shuttle to take evasive maneuvers from time to time.
But I know what I'd be interested in, if I were a developing nation with orbital capability. The space around Earth is turning into the next big salvage yard, especially if the costs of this mission are comparable to a high-profile terrestrial salvage operation. What better way to find out what other nations have been doing in the space above your country, than to grab a few samples of their equipment?
It's even better than a earthbound salvage operation, because there's no weathering beyond radiation and collisions with other pieces of debris. A defunct spy satellite would be in as good a condition now as it was the day it entered orbit, especially in terms of reverse-engineering. The chips may have a few bits shorted out, but the circuit boards, wiring harnesses, optics, propulsion systems, and so on could hold a trove of information.
And there's one thing I'm dying to do -- buy space knicknacks. NASA and the Russians could probably fund a significant space program by simply selling off that ton or so of "trash" brought back by each shuttle mission or burnt up in the used Progress craft. If India can bring back space nuts, old thruster bells, and the like, they could make a killing on eBay!
Stressed? Me? Of course not. Stress is what a rubber band feels before it breaks, silly.
It's nice to think of this as practical from the perspective of cleaning up space debris, but the real point of this is almost certainly for India to show that they have the ability to take out sattelites they don't like, much like the early Soviet and American sub-orbital flights and sattelite launches were demonstrations that we could drop explosive devices on each other from halfway around the world. Don't assume that something this complex and costly is being done out of the kindness of the Indian government's heard, or for the good of humanity when there's an obvious military benefit; especially considering their current cold war with Pakistan, and the technological escilation in China.
Hmmm... figuring out the optimal set of manuveurs to catch a set of debris objects that are all in different orbits would be very tricky.
I'm picturing it towing a huge red horsehoe magnet on a string, with all kinds of dead satellites stuck to it.
Really, while it's nice in concept to talk about cleaning up Earth orbit, the real danger is from the bits we can't even find, never mind capture, like paint chips. Sure, they only mass a few grams, but get a few grams travelling at a few km/s in one direction, and a spacecraft travelling a few km/s in the other, then do the math to find out the total kinetic energy of the system. (Hint: KE = 0.5 * m * v^2) Fortunately, space is big, but we're still doing our best to clutter it up, especially in LEO.
What we need is a satellite with a really big version of one of those pool skimmer thingies.
-Carolyn
Like Daddy always said: if you can't dazzle 'em with brilliance, baffle 'em with bullshit.
This doesn't really seem like a good application for ion engines. They are designed more for long distance deep space travel as they build speed very slowly.
This device will probably have more conventional thruster units that allow for high thrust and greater manueverability - especially if trying to catch objects that are no longer in orbit.
Here is a comparison of space engine capabilities: Engine Comparisons.
This device will probably have more conventional thruster units that allow for high thrust and greater manueverability - especially if trying to catch objects that are no longer in orbit.
Well, technically, if it's up there, it's "in orbit" around the Earth's center of gravity. It just may be the case that at some point in the object's orbit, the distance to the center of the earth is less than the earth's radius!
The problem with the low-power ion engine would be conservation of momentum, I'd think (though I'm not any sort of expert). If the craft is moving "forward", and the object it encounters is at the same altitude but moving "backward", capturing the object will cause some sort of change in the momentum of both objects.
The small object will abruptly begin moving in the opposite direction (unless it punches a hole in yer scoop!), but its kinetic energy (???) will slow down the big object. Just like the atmosphere, thin as it is, exerts a drag on objects in orbit that's proportional to the number of atoms hitting the object (which is proportional to the object's surface area).
That's when orbital mechanics kicks in. The slower you go, the smaller your orbit. Each "hit" sends the catcher closer to a fiery end, kind of like a celestial Slashdot effect.
Also, how will the satellite "catch" its targets?You can't just step on the accelerator to catch up to something, because increasing your orbital velocity increases your altitude. To go "up", you have to accelerate forward, to go "down", you have to accelerate backward, and I still don't fully understand what happens when you accelerate in some direction outside your orbital path!
All this is facinating, but boy, does it make my head spin...
Stressed? Me? Of course not. Stress is what a rubber band feels before it breaks, silly.
If the robot could capture the debris, and put it all in some kind of framework, a 'junk warehouse' if you will.. It could be a fantastic way to aquire raw material in orbit without having to pay much of the shipping cost.
Maybe it is worth comparing the design of this robot to the Indian one. It was discussed in this slashdot thread entitled Inspection Microsat Tested In Orbit.