Slashdot Mirror
Satellites Collide In Orbit
DrEnter writes "According to this story on Yahoo, two communications satellites collided in orbit, resulting in two large clouds of debris. The new threat from these debris clouds hasn't been fully determined yet. From the article, 'The collision involved an Iridium commercial satellite, which was launched in 1997, and a Russian satellite launched in 1993 and believed to be nonfunctioning. Each satellite weighed well over 1,000 pounds.' This is the fifth spacecraft/satellite collision to occur in space, but the other four were all fairly minor by comparison."
Hopefully the wreckage from this one doesn't end up causing any unpleasant chain reactions. Not only are satellites really expensive, we currently have no especially good way of ridding ourselves of orbital debris. It would suck to fill our good bits of orbit with trash.
That would probably be better than all the debris spreading out and remaining in orbit. That debris, now hundreds of individual pieces, is now able to cause trouble to anything trying to pass through its 'air space', including more satellites, etc.
Some say that the day we have combat/war in space is the last day we will enter space because the debris will block exit/entry.
I know they can FEEL endless when you're in them, but suburbs do not actually take up most of the earth's surface. The chances of that happening are fairly low.
I don't have the probabilities off hand but it is more likely than one might think at first glance. The set altitudes that are useful is not that large, especially for satellites that have the same job (in this case, communication). Furthermore, satellites are circling repeatedly so there are many opportunities where orbits will cross paths. That said, if I were the owners of the Iridium satellite I'd be pissed off right now. They've just lost a very expensive piece of equipment in what should be a preventable mishap. Somebody is going to get fired.
Are not the Iridium (and I will assume the Russian satellite as well) very low-orbiting satellites? This would mean the orbits will decay rather rapidly making this really not that big of a deal over the long term?
Some of the pieces will have gained orbital momentum and go higher, but really most of it should be getting some atmospheric drag and decay quickly.
Yes, these were in what would be considered low earth orbit. How much of a problem this is going to be depends on how many other objects are in nearby orbits that may collide with part of this cloud. The thing about atmospheric drag is that the atmosphere isn't really all that uniform. How a chunk of wrecked satellite with an unknown shape and size is going to react can be predicted, but only to a certain extent. Yes, everything will eventually fall down, even the stuff in a "higher orbit." Those orbits were just made more elliptical, and will eventually come down to about the same altitude the collision happened at. It's going to take awhile though, and those pieces that are too small to track are going to spread over wider and wider areas until they finally reenter. People will be furiously calculating probabilities of collisions for a long time. Decaying 'quickly' is relative I guess, while there is drag to bring them down, pieces will still be up there for years.
Not for much longer, if we have anything to do with it!
It composition may become not very useful to us but its not going to escape the gravity well anytime soon.
I was a bit skeptical about this, but I did the math. A large grain of sand (0.03g) would have the same kinetic energy of a 9mm slug at roughly 5.8km/s.
Orbital velocity at 10K km is 4.93km/s, so it's a reasonable value - and the relative velocity could be doubled if the objects collided head-on.
Now, I'm sure the shuttle could take shots from a 9mm fine and that much of the energy wouldn't be deposited - it would vaporize the much less massive object, after all. Of course, all of the energy would be concentrated in a very small area and could do a lot of damage...
Really fascinating. I should be sleeping at 3am, however, rather than calculating orbital impact energies on the back of an envelope...
Only on Slashdot could something so paranoid, full of speculation and even illogical when you take the facts into account get modded insightful, not once, but twice.
I'm not even sure what's so difficult to believe about two satellites colliding when there's so many up there. Even two relatively highly maneuverable manned planes collided in the UK a day or two ago, so it doesn't seem that difficult to think that two much less maneuverable, one of which no longer even active and working, unmanned objects might be able to collide.
Putin has spent the last few years selling himself in martial arts videos, showing off his ability to shoot tigers, flexing his muscles whilst fishing and many other such show off type things. Don't you think he'd jump at the chance to say "Hey, by the way, Russia just show down a satellite too?". Even if they realised they screwed up by somehow hitting a commercial satellite too don't you think the commercial satellite owners would say something? don't you think the US, China and millions of other people capable of tracking such events would scream at the chance to say "Russia just flung something into space and taken out a civilian satellite"?
I don't even see what's so coincidental about the timing, what's so special that now, over 2 years after China did it would be a good time for Russia to have a pop at it again too? Is there something special about around 2 years and 3 weeks later that allows it to be defined as coincidental?
But there's a bigger problem with your theory, ASAT technology isn't even new, the Russians built ASAT kit back in the 60s, 70s and 80s, the US has had F15 launchable ASAT missiles since at least the 80s, possibly the 70s. In fact, looking at Wikipedia (http://en.wikipedia.org/wiki/Anti-satellite_weapon#USSR.2FRussia) it states Russia has pulled off 23 test launches and has had an operaitonal ASAT system since 1973.
If anyone's going to show off ASAT capability next it'll be somewhere like Iran or India most likely. I like people who think outside the box and come up with new ideas but come on if we're going to have conspiracy theories and mod them insightful let's at least have them consist of some degree of plausibility and at least make some sense please?
Who would have thought that simply discarding waste would ever become a problem?
An SQL query goes to a bar, walks up to a table and asks, "Mind if I join you?"
IAAParticle Physicist, working on the Collider Detector at Fermilab, looking for the Higgs boson. Am I sufficiently credentialed for you, or will you "call my bluff" like the poor AC below? Electrostatic forces are an effect of the electromagnetic (or to go even further, the electroweak) interaction. GP is correct, P is incorrect.
Usually, the four fundamental interactions are given as gravity, electromagnetism, and the weak and strong nuclear interactions. At high enough energies, electromagnetism and the weak nuclear interaction turn out to be the same thing. At even higher energies, maybe the others will merge in as well.
Except gravity, these interactions have pretty well understood quantum field theoretic descriptions, motivated by particular symmetries (and their breaking sometimes), involving the exchange of momentum and other quantum numbers via various particles (the gauge bosons). The gauge boson responsible for the electromagnetic interaction is the well known photon.
But you don't have to take my word for it. Please run down to your local library and pick up a copy of John David Jackson's _Classical Electrodynamics_, and a copy of Peskin and Shroeder's _Quantum Field Theory_. These are the standard graduate textbooks for their respective fields, and will provide all the detail you might wish to find.
Also, in the future, please look these things up before spouting off what you remember from your "year 10 science" class. You probably don't remember it correctly, if today is any indication.
SIGSEGV caught, terminating
wait... not that kind of sig.