Shiny New Space Fence To Monitor Orbiting Junk

coondoggie writes "Some work has begun on tracking and detecting the overabundance of space junk which has become a growing priority as all manner of satellites, rockets and possible commercial space shots are promised in the coming few years. Today Northrop Grumman said it grabbed $30 million from the US Air Force to start developing the first phase of a global space surveillance ground radar system. The new S-Band Space Fence is part of the Department of Defense's effort to detect and track what are known as resident space objects (RSO), consisting of thousands of pieces of space debris as well as commercial and military satellites. The new Space Fence will replace the current VHF Air Force Space Surveillance System built in 1961."

Deorbit

[Bruce Perens]

We need to work on how to de-orbit it. My favorite scheme is to use infrared lasers to apply light pressure, and slowly change the orbit.

Re:Deorbit

[vrmlguy]

Launch water. You don't need to put the water into orbit, just release it in the path of whatever debris you want to deorbit and let your launcher fall back to earth. The debris loses velocity as it passes through a cloud of H2O molecules and slows down enough to re-enter the atmosphere. Sine you don't need the delta-v, the launches are fairly cheap, at least as long as we're at low altitudes.

Re:Deorbit

[MichaelSmith]

I definitely agree with the general idea but I am concerned that not enough water would sublimate during a suborbital lob. Ideally you want your payload to be liquid or solid at launch to save on structure in the launcher. You could pack it with an explosive but that got me thinking about this coke bottle which was in the back of my car rolling from side to side for hours until I cracked the seal and got myself covered with sticky muck.

So maybe we need a mixture of CO2 and H2O at moderate pressure to get maximum dispersion. Of course lots of countries are showing off their sounding rockets right now. Maybe this is a good job for them.

Re:Deorbit

[MichaelSmith]

Its expensive to get water into orbit. It is much less expensive to get it directly into space so it falls straight back. You don't want it to be in orbit anyway. You just want a cloud which the debris goes through.

Trapped on earth

[EZLeeAmused]

Didn't Arthur C. Clark or someone theorize that at some point in any space-faring civilization, they would lose (at least temporarily) the ability to return to space due to the density of debris orbiting their planet?

Planetes

[psnyder]

There's an award winning anime/manga series called Planetes [wikipedia.org] that deals with this very problem. It's about the people whose job it will be to dispose of the detected debris (usually by burning it via atmospheric reentry or through salvage) before it collides into something.

Re:Here in the UK...

[Bakkster]

Everything then was mundane as it is now, and the old technology worked very well. Supposedly objects about a half metre were tracked, but that was "classified" information at the time.

Did you actually read the article? The current system tracks objects 4 inches and larger in diameter. The new system will track objects as small as 1/2 inch in diameter.

FTA:
"the United States Space Surveillance Network, managed by U.S. Strategic Command, is tracking more than 19,000 objects in orbit about the Earth, of which approximately 95 percent represent some form of debris. However, these are only the larger pieces of space debris, typically four inches or more in diameter. The number of debris as small as half an inch exceeds 300,000. Due to the tremendous energies possessed by space debris, the collision between a piece of debris only a half-inch in diameter and an operational spacecraft, piloted by humans or robotic, has the potential for catastrophic consequences, he stated."

It would appear to me that an American corporation is just trying to get yet another contract to do the same thing that they have been doing for years. VHF/UHF has some disadvantages, but the system in place is (or at least was) similar to the UK's. It looks like yet another money grab by the contractors to replace something that is fully functional and could operate for a generation or two at a nominal cost. What, after all, is a mere $30 million USD, though?

FTA:
"The current system requires constant sustainment intervention to maintain operations and does not address the growing population of small and micro satellites in orbit, Northrop stated."

At some point, maintenence costs on big systems like these get too high. A replacement system will not only operate better, but cheaper. Either replace it now and shut off the old system when we're done, or wait until the old system fails and scramble to build a new system (rushed development produces errors and costs more).