Real life kessler problem.

[togfox]

http://redux.com/stream/item/2130523/Did-you-know-there-were-this-many-satellites-in-orbit-VIDEO

[Elven_sword]

When you consider how much distance is really between them, it\'s not that much of a problem. Still a problem, but with modern tracking tech we can put launch windows in between satellite orbit.

[Amram]

http://curator.jsc.nasa.gov/seh/index.cfm

LDEF, Nasa left it in orbit for close to 6 years, in that time, in 2100 days, it suffered 20,000 some impacts. An average of almost 10 per day, or 1 every 2.5 hours.

We don\'t really need all that much more up there, its cluttered enough already. Although afaik we have a couple of parking orbits for satellites that are about to die for whatever reason.

http://www.nasa.gov/centers/wstf/laboratories/hypervelocity/mmod.html

http://www.nasa.gov/centers/wstf/images/content/283134main_Earth%20Beehive.gif

approximately 95% of those are non functional satellites, just debris...

ISS, and most satellites have at least limited maneuvering capabilities, and these days, they are almost essential to a long life in orbit. In the last year, the ISS has maneuvered 4 times, and would have maneuvered a further two if warning had been sooner. And all a man made threat, not space rocks or such.

http://orbitaldebris.jsc.nasa.gov/newsletter/pdfs/ODQNv16i2.pdf

The chinese anti satellite test a couple years ago produced a not insignificant amount of debris either. Half the catalogued debris that re-entered resulted from that event.

When Cosmos 2421 broke up, it became 500 pieces of debris, those leave us with an impressive exponential growth if it ever got out of hand.

Four times in the last 5 years chinese rockets have blown up in the middle of orbital insertions depositing alot more debris, and will likely continue to do so.

There are 2080 tracked items in orbit, an unknown number of untracked items. of those tracked, nearly all of them spend time between 600 and 800km. nonne have a perigee above 800km. With high solar activity, anything below 800km can experience a noticeable amount of drag.

The point?

low earth orbit, the first stop for nearly everything we do in space is only going to get busier, whether or not we continue to leave junk in space. Most of what we put up there hasn\'t made it that far on the journey home. Will they? Yes, they will, none are high enough to be 100% out of the atmosphere, although some will take a very very long time to return.

As the bulk of these occupy the same approximate orbital range, they\'ll come down in a fairly small span of time when compared tot he time that will be needed for all current debris to come down. At some point in the future there will be a significant increase in threat than there is now. And it seems unlikely to me(although I am not qualified to even hazard a guess at time span) that this peak in threat will end after only a year or two, likely there will be much greater threat for decades, if not centuries, barring human intervention.

As of April 2012, more than 1/3 of all debris is chinese(.....maybe if the long march series stopped blowing up....), but nearly all is accounted for by totaling US, Russian, and Chinese debris.