Every now and again someone raises a stern warning about the amount of space junk orbiting Earth. Those warnings are usually met with general indifference, as very few of us own satellites or travel regularly to low Earth orbit. But the DoD's assessment of the space junk problem finds that perhaps we should be paying attention: space junk has reached a critical tipping point that could result in a cataclysmic chain reaction that brings everyday life on Earth to a grinding halt.
Our reliance on satellites goes beyond the obvious. We depend on them for television signals, the evening weather report, and to find our houses on Google Earth when we're bored at work. But behind the scenes, they also inform our warfighting capabilities, keep track of the global shipping networks that keep our economies humming, and help us get to the places we need to get to via GPS.
According to the DoD's interim Space Posture Review, that could all come crashing down. Literally. Our satellites are sorely outnumbered by space debris, to the tune of 370,000 pieces of junk up there versus 1,100 satellites. That junk ranges from nuts and bolts lost during spacewalks to pieces of older satellites to whole satellites that no longer function, and it's all whipping around the Earth at a rate of about 4.8 miles per second.
The fear is that with so much junk already up there, a collision is numerically probable at some point. Two large pieces of junk colliding could theoretically send thousands more potential satellite killers into orbit, and those could in turn collide with other pieces of junk or with satellites, unleashing another swarm of debris. You get the idea.
To give an idea of how quickly a chain reaction could get out hand consider this: in February of last year a defunct Russian satellite collided with a communications satellite, turning 2 orbiting craft into 1,500 pieces of junk. The Chinese missile test that obliterated a satellite in 2007 spawned 100 times more than that, scattering 150,000 pieces of debris.
If a chain reaction got out of control up there, it could very quickly sever our communications, our GPS system (upon which the U.S. military heavily relies), and cripple the global economy (not to mention destroy the $250 billion space services industry), and whole orbits could be rendered unusable, potentially making some places on Earth technological dead zones.
I am exponentially more bothered by the destruction of life and viable land due to the growing mountains of refuse here on the surface. In either case, it's unjustifiably trashy behavior that has to stop.
My drive home takes me through a low-income part of the county built on top of an old landfill from the '80s. On hot days, the ground ripples and belches gas, sometimes forming giant gas "blisters" in people's lawns. Most of the people have sold their property and moved over the years. Some still tolerate the nauseating smells and dizziness-inducing gases. Many of the children in the area are born with defects and/or learning disabilities. It's sickening. Hundreds and hundreds of acres now sit empty, and even the trees struggle to live. During last winter's snow storm, the only trees that toppled were in that stretch of land.
We'll manage to survive if our satellites die...
Reduce, reuse, recycle, people. The only person who can make a difference is you.
Don't have a recycling center near you? Start a petition.
I got over feeling helpless and started doing all I can to make a difference....
you should, too.
Jeeze thanks China you almost doubled the amount of junk in space with that careless stupid idea to blast it apart with a missle.
Just goes to show you what would happen if we tried nuking a meteor someday. Zillions of pieces and more damage than left alone.
ur tellin me lol. I live in the Atlanta area, which is the nation's most toxic area with the most EPA Superfund Sites. It's really sad actually. I'm not some eco-green fenatic or a tree hugger or anything but i believe that God gave us this Earth and he didn't make it for us to destroy. I like doing things outside and enjoying hikes and camping and things like that. But at the rate we're at, our children will never get to enjoy these great activities that we consider essential to growing up that we just take for granted. Seriously, it doesn't take much effort to not destroy the land. Dispose of waste properly. Recycle. And be careful when constructing buildings and such.
I probably won't get a response here but are the Agena boosters from the Gemini program still up there?
I'm not sure a chain reaction is likely - this is not an enclosed space, and it is not occurring on a 2 dimensional surface.
I'm assuming if these fears were real someone would have easily produced a nice computer simulation showing it happening. Why haven't they?
There are to many ifs in this article. It's all empty speculation.
We need to grow a big space sponge to trap all debris.
I love watching Dominoes
If 2 objects in orbit slammed into each other orbiting in opposite directions it would be about a 35 thousand mph collision, assuming orbital velocity of about 17,000+ mph, and send stuff flying all over the place, and probably knock both of them, what's left of them, out of orbit or into the atmosphere.
If 2 objects collided that were on orbits 90 degrees from that's about a 25,000 mph collision.
If they're approaching each other at 45 degrees it'd be about a 13,000 mph.
At 10 degrees angle of incidence it's still around a 6000 mph collision.
At 1 degree angle of incidence, 2 objects orbiting at 17,000 mph would slam into each other at about 600 mph.
Seems to me the slower collisions might be more dangerous, where debris might not be ejected out of orbit or into the atmosphere, but instead just spread out and staying in a range of stable to unstable orbits.
Math is fun!
Sorry screwed up my math.
10 degrees = 3000 mph collision.
1 degree = 300 mph collision
I'm just using simple trig:
collision speed = (sin [angle of incidence / 2] * orbital velocity) * 2
can there ever be a internet discusion where someone doesn't bring up their stupid god? god is a superstition. like unicorns and gremlins.
Can't someone on these boards mention God without some idiot troll so ignorant and insecure in his atheism that he feels the need to flame them? It makes sense for a theist to flame an atheist, but it does not make sense for an ateist to flame a theist. Does imagination really offend you so much? Are you also flaming the unicorn believers over on the CareBear web blogs? Idiot.
If two object collide, assuming they are both small, solid objects (like screws), then they would need a cossal impact speed at just the right angle, otherwise, they would just bounce off of each other.
Even given a more spectacular collision, space is really, really, big - a shotgun blast of detritus is going to spread out into space, down into the atmosphere, and around in orbit, making subsequent collisions less and less likely the furth the other objects are from the impact zone.
Yes, it is getting more and more crowded up there, but space continues to be really really big.
The image is really exaggerated.
eventually, we might get a second moon made out of scrap metals
I like how the chinese apparently doubled the number of debris in space with that missile... awesome ! I think at least the internet doesn't rely on satellites ( well besides obvious stuff like google earth) so we'll still have that for communication :)
Craigboy - no, those early missions were so low that those stages have long since decayed.
Cosmovideo - the image is realistic in that depicts the number and orbits of catalog debris (essentially items >10cm or so), but exaggerated in the sense that the size of each piece of debris has to represented by at least 1 pixel, which may of course not be to scale.
Cofoundicator - in hypervelocity collisions - those where the closing velocity exceeds the speed of sound in the materials of the objects by several times - there is virtually no transfer of momentum from one object to another - they more-or-less 'pass-through' each other, sending shockwaves through each body that distintegrates each into swarms of debris. Thus very little mass is either 'knocked out of orbit' or picks up additional energy to change its orbit. This is why the concept of a massive runaway chain reaction is unlikely - the debris in any particular orbital energy band will not affect satellites in other bands. You could have problems if an ASAT was injected into circular orbit at the same altitude as the GPS constellation, but otherwise collisions are unlikely.
Hmm..Intuitive solutions distorted by a 1 G field
and low speed interactions; Even vaporizing all the
junk might have unintended negative consequences.
Somebody with orbital mechanics math skills;
How large a swept area could a capture disk have
before the difference in speed of objects in higher
and lower orbits became destructive ?
I for one completely agree with Boka. This is a science based website, and it doesn't need any theistic morons clogging up the comments board with their self righteous claims. People like you piss me off to no end. Where do you get off selling shit like: "It makes sense for a theist to flame an atheist, but it does not make sense for an ateist to flame a theist." Really? Why don't you run back to your tv evangelist special and let the grownups talk.
Not to worry... as soon as China owns earth orbit they will cleanh up all the debris. With US abandoning any means to put men in space, it won't be long before that happens.
Im surprised they havent developed a lazer that they can hit space junk with and vaporize it.
Just a bit of clarification. A runaway reaction is definitely possible in low earth orbit (which is where the shuttle, space station, and most weather and imaging satellites reside), and is known as a "Kessler Syndrome." There is debate over whether or not we have reached the tipping point, but it is an important issue to track.
However, a runaway reaction in medium earth orbit (GPS satellites only) or in geosynchronous orbit (where most communications and TV satellites reside) is not a possibility because these orbits are much much higher up, have a far lower density of satellites and debris, and are much less "chaotic" than low earth orbit.
Funny how no one mentions the US military used missiles to destroy orbiting satellites in TWO separate occasions that were made public (probably more in secret). One in September 13, 1985 and another in February 21, 2008.
Of course anything the US does is okay, but if someone else does the same thing its "a huge environmental concern" and everyone is so quick to criticize without looking at their own country first....
To wade in yet a-freakin'gain. The largest complaint about religion I hear is people saying that it's shoving their views on others. You do know that atheism IS a religion, and thanks to some guy in california that started the church of atheism (though how does that work the a-pastor stands up, opens his mouth, shrugs his shoulders and says meh, and a rousing a-amen erupts from the a-congregation) is an official religion.
The atheist religion is as full of zealots who preach their beliefs as any of the most cult-like religion of any other variety.
That is your belief, your faith. That's ok, whatever. But to preach that your atheist faith is the correct one and all other's is wrong, you ARE everything you say is the worst about other religions.
Other religions are up front that it is a faith, a belief. You like science, me too, here's how it works hypothesis->test->conclusion. There is no test possible for the existence of God, so no scientific conclusion can be reached. To believe or disbelieve is a matter of faith and belief, other religions aside from the atheist religion don't claim anything different.
From my posts you can figure I believe in religion. But you have no idea what my faith is, christian, buddhist, shinto, old norse. I don't push my belief system on anyone, and I expect the same respect from you. If you would like a polite debate, that's fun and interesting, but to announce your own correctness, and everyone else is wrong I don't like that with any religion including the atheist religion.
So how about we allow anyone who comments POLITELY on their religion whether christian, buddhist, atheist.... not to be jumped on unless their being pricks about it.
What say you to that.
Now that's what I call some Holy Crap!....I see a new business venture for the Astronaut Farmer....'The Holy Crap Space Shuttle Cleaner'....Hey,...It can happen!... :-)
This graphic was first produced in the 1980's by Teledyne Brown Engineering. It was in black and white, then. I have always thought it was a bunch of hogwash designed to scare Congress into funding certain NASA offices and taking actions that were not necessarily in the public interest.
At that point-pre 1984, NASA wanted information on how close junk might come to the shuttle, but never maneuvered to avoid it. Challenger changed that.
In 1989, Congress directed a study of orbital debris. NASA wanted it to say that orbital debris grew at an exponential rate of 8% a year and that the space environment would be inhospitable by 2050. They used some clever data to get to those numbers.
This article doesn't mention it, but there is a natural mechanism for cleaning out low earth orbits. It is the 11 year solar cycle which causes Earths atmosphere to expand significantly during part of it, increasing drag and causing junk to deorbit.
NASA was so dishonest that it cherry picked the data to exclude the sun cycle atmospheric years, beginning just after the end of one expansion and ending before the next one started, which is how they got their 8% growth rate. .
A more honest graph of the annual numbers of space objects over the whole history of space flight up to that time, provided to me by Nick Johnson of TBE, showed a linear growth rate, not an exponential growth rate.
NASA contractors generated a clever simulation to support their numbers. Their gimmick was that it completely discounted conservation of mass in collisions. Every new piece generated by a collision had as much mass as the original satellite. It is as though the Chinese ASAT created 150,000 (if you believe that number-I don't) new objects, each object having as much mass as the original satellites and capable of causing another major collision.
NASA doesn't mention this often, but a small piece of debris caused them to replace a shuttle window-but it didn't destroy the shuttle. Even if there are 150,000 new objects from the Chinese test, the vast majority won't cause new objects even if they collide with an unpressurized satellite, though they could disable the satellite.
I wouldn't expect the author of this article to be familiar with the nuances of my comments-there are probably people in the space industry who are not-but he might ask NASA for a graph of the number of trackable (cataloged) objects in orbit each year from 1957 to the present.
My experience with the NASA report to Congress completely destroyed my faith in anything that organization puts out that might have a political implication. They are political animals in search of a budget, not scientists, and taxpayers would be well to understand that.
Care to bet that people can identify me?
NASA also had a simulation that supported the
The answer is a giant laser to vaporize debris in space.
"You do know that atheism IS a religion, and thanks to some guy in california that started the church of atheism (though how does that work the a-pastor stands up, opens his mouth, shrugs his shoulders and says meh, and a rousing a-amen erupts from the a-congregation) is an official religion"
actually the church of atheism ISN'T about religion. Seven years ago, three former Catholics and a former Methodist established a church for those who don't believe in God. They had all left religion after losing their faith, but they still wanted a "Sunday morning experience" where they could enjoy the fellowship and sense of belonging that comes with church attendance.They call themselves a "church for the unchurched," where nonbelievers can gather on Sunday mornings for the same social and community benefits that other churchgoers enjoy. It's about community nothing to do with pasters shrugging there shoulders and saying mey a-ahmen. Next time you try to tell people not to harp on others religions why don't you try not to harp on other peoples two paragraphs earlier in the same post. You my friend need not try to "wade in" ever a-freakin-gain.
I always thought it'd be funny one on of those alien invasion shows or movies if the alien fleet suddenly reported "Our ships are being smashed to bits by a ring of debris! All hands abandon ship!"
Athiests: the most self righteous assholes on the internet.
This issue keeps coming up, and I wish we had a government agency that could get a handle on how to clear the debris from overhead in a sane manner. Oh, wait--thanks again, NASA. Now that we've spent ourselves into oblivion, we've gotta cut your funding.
If they really want to save things like the Atlantis, give it a space debris mission. The money we would lose if the telecommunications systems of the world were to collapse because of an outage would make it worthwhile to do something other than complain about the problem.
Reminds me when in an unprecedented space collision, a commercial Iridium communications satellite and a defunct Russian satellite ran into each other above northern Siberia, creating a cloud of wreckage.