
Purpose
The NanoSail-D has the far more nefarious purpose of eliminating the operating spacecraft of other countries. It illustrates the arrogance of my country that we view any other satellites as rubbish.
NASA has successfully tested an extraterrestrial rubbish collector that could sweep up the star system's space debris. The agency's NanoSail-D is a teeny satellite that deployed the first-ever solar sail in low-Earth orbit and sailed around the planet for more than 240 days. The sail is NASA's idea for cleaning up …
Is this sail to be fitted to satellites that have to be taken out of commission?
Or does this sail do the sweeping of small bits and pieces while gliding gently in orbit accompanied by the 'blue danube' waltz?
If those pieces are that harmless that they can be caught by a sail, why are the ISS inhabitants so afraid of this stuff?
THe headline makes it sound like it reduces current rubbish, but it actually just prevents itself from being rubbish in future.
Seems like more hassle than a small rocket to push it out of orbit instead of hacking around in orbit for weeks while a giant sail slows it down.
The sail is presumably nowhere near strong enough to stop high-speed debris.
I suppose if it is pre-accelerated to the debris-in-question's speed and then gets n front of it and deploys sail the interaction could be gentle enough for sail to survive. More likely to send sail-sat spinning off and colliding with other junk though.
My tuppence.
its relative, i dont know if people considered the direction of travel when popping crap up there but if its all going teh same when then all you need to do is send this thing only slightly faster than the junk and it will pick it up nicely, like a giant road sweeper, i think the chaps on the ISS are more worried about stuff that is flying, relitively speaking, much much quicker, in the order of thousands of mph, which were it to hit it would be a problem, no matter how big the junk was, also i assume that this would be more suited at catching all those nuts, bolts, spanners and golf balls flying around rather than car sized satilites. cool idea tho, hope it works, but one thing NASA, you need to find someone else to do your voice overs, there was something about that guy that was kinda annoying
"NASA has successfully tested an extraterrestrial rubbish collector that could sweep up the star system's space debris."
This is TOTALLY untrue.
All they have done is demonstrate a method for FUTURE satellites at end-of-life to deorbit 'for free' in a reasonably short time by deploying something like a drag-chute.
(The life of the satellite is also extended because it can now use all its fuel for station keeping instead of having to safe some for deorbit)
Sweeping up existing space debris is practically impossible because of the huge amount of energy required to match a target's orbit before it could be collected. Colliding with it just makes orders of magnitude more pieces of debris to clean up.
However, there is a possible way to mop up debris that may be remotely affordable.
Foams in a vacuum can grow to enormous volumes of really really negligible density, so just launch and extrude thousands of kilometre-sized foam blobs with a couple of tons of reagents into safe high orbits.
They would absorb enough detrital kinetic energy to either capture or deorbit them, perhaps about once per day, though some junk travels in families or have convergence points.
However, they will decay very quickly, and be knocked about a bit and spall, their rotation and orbit may become unpredictable, but any fragments will be so light and fluffy they should be much less of a hazard than the junk and decay very quickly.
If these could be built - the material would have to withstand extremes of temperature, and would deform massively as the gas bubbles expand and contract near the surface.
However, even with thousands of these things, the volume is so vast that it would take centuries to make space 'safe' again. Do the maths!
Actually, despite the article talking about ways of sweeping clean Low Earth Orbit, a quick look at wikipedia (find it yourself, I'm too lazy to give you the link) shows that everyone just wanted to get some data on how solar sails operated, even if on a small scale.
If there was some debris swept up/deorbited/whatever, then the article writer should update and either explain more or offer a link to somone/somewhere that mentions NanoSail-D2 bringing down a few bits and pieces.
The key thing to take away from this is that the concept of the solar sail has been vindicated, and further experiments into using them as a way to provide propulsion for spacecraft can now take place.
This could well turn out to be one of the major experiments in the future of spaceflight for the next generation.