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Giant Balloons Could Solve Space Junk Problem
An anonymous reader writes "More than 100,000 objects bigger than a centimeter wide hover around our planet, accounting for 4 million pounds of junk that befouls our atmosphere and threatens the expensive satellites we actually want in orbit. Dr. Kristen Gates, of Global Aerospace Corporation, proposes that we can clear the skies by attaching a football field-sized balloon to dead satellites, which would increase the orbital drag, eventually bringing a satellite down into the atmosphere where it would burn up. The GOLD — or Gossamer Orbit Lowering Device — unit is easily inflated in space, and best of all, if the deployed GOLD balloon collides with space junk, it won't deflate or break the junk into smaller, less manageable bits."
With no pressure on the outside of the balloon it would deflate very slowly. This is doubly so because it does not take much gas to inflate a balloon in space due to the lack of outside pressure.
Also they have developed materials that, once inflated in the vacuum of space, can hold their shape without any internal pressure.
Actually most spacecraft (including "secret" government satellites) are tracked by both governments and private entities. Since the last collision the US Air Force has actually started expanding their capability for this even more. They are very open to working with other parties to solve space debris issues and avoid collisions with their satellites or between other satellites.
I'm having a problem understanding how filling low-earth-orbit with Zerg Overlords is a good thing.
Some mornings it's hardly worth chewing through the restraints to get out of bed.
What I don't understand is, since we already paid a hefty price to lift this "material" into space, why not collect it in orbit and save it until we can utilize it as raw materials for future space projects. There must be lots of useful stuff that could be reprocessed and reused.
Doesn't everyone have the expectation that we will have factories in space to build the things that are needed in space from raw materials gathered from around the solar system? This would just be raw materials for those factories that doesn't have to be lifted out of the gravity well of earth.
Because it will never catch them?
You can test this at home with this simple procedure.
1. Get a sheet of mylar and some sticks, an emergency blanket will do.
2. Using the mylar and some sticks make a your balloon. The sticks will help to simulate the structures that can hold their shape.
3. Tie this off to any structure. That structure will be the stand in satellite.
4. Cover the balloon in glue.
5. Get out your favorite high power firearm and fire some rounds at the balloon. These will be the space junk.
6. see if any bullets, your simulated space junk, got stuck in the glue
Why not simply magnetize the dead satellite or include a small permanent magnet? This would create a magnetic sail. The magnetic field around the satellite would slowly trap plasma from the trace of gases and ions in earth orbit, as well as anything leaking from the sat itself. This would inflate the magnetic field lines and expand a kind of mini magnetosphere around the satellite. This would create drag against the earths magnetic field, and outer atmosphere.
Common permanent magnets can be much stronger than needed for this.
http://en.wikipedia.org/wiki/magnetic_sail
After logging in slashdot still does not take you back to the page you were on. It's been that way for 20 years.
abelenky17 is off-base. The ones most likely to be of interest are also the largest (and generally most-capable) units, which would require the most fuel to move. Mercury SIGINT satellites are around five tons, and the Lacrosse synthetic aperture radar satellites reportedly mass up to 16 tons, and both are in LEO.
This isn't to say that they cannot change orbits, just that it requires a very good reason to do so, as not only does it use up precious fuel, but like any operational satellite it has scheduled uses. They're never put up there "just in case we need them."
It's also not to say that there is no use for highly-variable orbits. That the Air Force has been playing with their recently-launched toy shows as much. It's just that such things are not trivial achievements. Such capabilities make it much harder to hide from overhead eyes. Lacrosse-5 has some kind of technology that allows it to "disappear" even in direct sunlight, which makes much more sense than loading it with tons of fuel, but still leaves it fairly predictable.
You can never go home again... but I guess you can shop there.
I wonder if you could coat the balloon with a cheap reflective material that would leave residue on debris that impacted the surface. Wouldn't that provide a gradual increase in our tracking ability without costing a whole lot more than the original design?
There are no astronauts, there are no robots, there is nothing extra being launched into orbit to intercept existing satellites. This is a small, couple kilogram, briefcase sized package that will be attached to new satellites at launch, so at the end of their life, the balloon will be deployed, and the satellite will de-orbit in a matter of weeks.
They should have designed these satellites to be self-killing - i.e. Burn a rocket, deorbit, and burn rather than just throw stuff all over the place & forget about it.
Satellites generally are designed to be self killing. All satellites have some sort of moderate delta-v rocket meant for station keeping and orbital maintenance. A significant amount of the fuel for this rocket is held in reserve, in order to de-orbit the satellite at the end of its life. Geosynchronous and other high orbit satellites cannot afford to re-enter, so instead they rise up to a 'graveyard' orbit, in order to keep the useful orbits clean. The purpose of this balloon is to replace the reserve fuel for low earth satellites. It is significantly lighter than the required fuel, so it will allow a higher payload fraction for the satellite.