Tipping Point Reached - Space Junk May Prevent Future Human Spaceflight

Space junk is a deadly menace to satellites, humans, and anything else that is orbiting our planet.  The number of pieces of orbital debris has been increasing every decade since the 1960’s.  The contents of orbital debris  range from dead satellites and spent rocket boosters at the large end of the spectrum, down to nuts and bolts at the small end.  This debris is so dangerous because it is traveling at speeds of 17,500 miles per hour or greater.  At these speeds objects as small as 0.2mm, like a fleck of paint, can penetrate a space suit or damage a window on a spacecraft.  When you consider that rifle bullets travel at a measly 2,000 mph you can imagine that a screw moving at 8 times the speed of a bullet can do serious damage to just about anything in orbit.  NASA estimates over 20,000 pieces of orbital debris larger than a softball and 500,000 larger than a marble.

The real danger from space debris is that every time there is a collision in space, it creates more and more debris.  Eventually it reaches a point where you can’t go anywhere in orbit without getting constantly hit by space debris.  This has been dubbed the Kessler Syndrome, after the retired head of NASA’s Orbital Debris Program.  According to Kessler “Space is becoming essential to our current civilization.  If for any reason we weren’t able to use satellites as easily as we do today, there would be a reduction in the standard of living.”   Even if we did nothing about space debris and didn’t ever make another space launch, the amount of debris would continue to increase due to the amount of material undergoing collisions.  The Kessler Syndrome isn’t a theory, it’s happening right now - except it’s in the early stages where it is still possible to reverse the trend if action is taken soon.

So, what can we do about this growing menace?  After all, according to space treaties, whoever launches the space junk is legally responsible for it and any damage it may cause.   Well, we can let it eventually fall to Earth at a random time and place, or do something about it ourselves. Star Tech Inc. has a plan.  EDDE is the ElectroDynamic Debris Eliminator and it promises 12 EDDEs could remove all Low Earth Orbit debris larger than 4 pounds in 7 years as shown in this simulation.  EDDE will use lightweight nets to capture debris and bring it to a lower orbit where it will let go of the debris so that it will naturally fall back to Earth due to atmospheric drag.  This project will use a type of propulsion called an Electrodynamic tether that uses the Earth’s magnetic field much like an electric motor.  EDDE will use differences in the Earth’s magnetic field at different altitudes produce electricity along a conducting tether, when this electricity is run along the tether it will interact with the Earth’s magnetic field making a force that can be controlled to move the entire spacecraft in any direction.  This has the much needed benefit of not requiring any fuel, which is necessary for this mission due to the EDDE spacecraft doing a great amount of moving around low Earth orbit to catch and release target spacecraft.
There are other ideas being researched to get rid of space junk. Russia’s Energia corp. may spend $2 Billion on a nuclear powered craft that will grab satellites and deorbit them.  It would target 600 satellites over a 15 year period.  That’s looking better than DARPA’s other ideas of launching rockets filled with water to create walls of ice that debris will run into and fall out of orbit, or shooting the water at the satellite and deorbit it that way.  Re-fueling satellites are currently undergoing testing and would also reduce waste in space by keeping satellites operational for longer periods of time.  Whatever technologies we decide to use, we are going to have to deal with this problem before we are enclosed in a sphere of deadly garbage. 
(above image) Here's one idea of what to do with all the left-over space junk.

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