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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."
These satellites were Iridium33 (24946) and K-2251 (22675). Now they are pieces of debris from bowling ball sized pieces to vapor.
A nice little animation of the collision is placed here:
http://i39.tinypic.com/2vbk75z.gif
This was bound to happen and will happen again. The interesting question is how come they didn't maneuver one of them out of the way. I don't know if 22675 is an active payload that still has power but Iridium33 certainly has the capability of moving. This one was avoidable. Even my non rocket science brain can take the TLEs and figure out that they were passing way too close to each other (I put it at about 500 meters with the latest elements).
Unfortunately, this didn't create 2 'clouds' of debris. This created one huge field of debris that will continue to expand over time. Many of the pieces will be tracked but the very small pieces cannot be.
It would have been way cool to observe the collision!
We currently have no especially good way of ridding ourselves of orbital debris.
That's why we need Debris Section
from the article: "Iridium Holdings LLC has a system of 65 active satellites which relay calls from portable phones that are about twice the size of a regular mobile phone. It has more than 300,000 subscribers. The U.S. Department of Defense is one of its largest customers." The collision occurred over Siberia.
"The ability to delude yourself may be an important survival tool" - Jane Wagner -
One of the Sat.s was a non funtioning sat. When the whole thing fails, you can't really deorbit it..cause it failed.
The Kruger Dunning explains most post on
I know of 3 previous collisions.
1991-12-23 COSMOS vs. COSMOS DEB (discovered in 2005)
1996-07-24 CERISE vs. Ariane R/B
2005-01-17 Thor Burner vs. CZ-4 DEB
What's the 4th previous??
When a satellite fails, often it cannot be de-orbited. Several failure modes will cause this - the most common is the malfunction of the controller, communications unit, or onboard power system. When any of these fail, there's no way to command the retro-rocket to fire.
Then, too, you need the satellite to be pointed in the correct direction (meaning that its stationkeeping rockets are working), and for it to have enough hydrazine (or whatever) to be deorbited. Near the end of a spacecraft's life, consumables are limited.
And, of course, it takes a lot of energy to de-orbit many satellites. A geostationary comsat needs one heck of a kick motor to get it down. Usually they are not brought down to burnup in the atmosphere. Instead, they are moved a few dozen (hundred?) kilometers inwards from their geostationary slot. This puts 'em well away from the main circle of geostationary satellites.
It's like consumer goods ... manufacturers work to make them last long enough to complete their mission; few think about how to get rid of 'em once their purpose has expired.
http://en.wikipedia.org/wiki/Will_It_Blend
http://en.wikipedia.org/wiki/Kessler_Syndrome
Sure, here: http://www.willitblend.com/
But... the future refused to change.
Yes, of course, they certainly ARE watching all satellites! You see, these birds cost something in the order of $100 million each, don't you think someone is being paid to take care of them?
Well, of course, if it's something between a broken satellite that never reached its intended orbit, and a satellite from a bankrupt company that never had any profit, that's different. It's not as if they were true operating satellites, is it?
we currently have no especially good way of ridding ourselves of orbital debris.
Gravity? Granted its slow, but it works. Everything in orbit now will be gone in, ooh, a century or so.
No. Everything low enough to exprience atmospheric drag will be gone in a century. Anything above 1000km will last thousands of years in orbit. Objects in geosynchronous orbit will last indefinitely because they can slide into valleys in the Earths gravitational field and stay there. Arthur C Clarke liked to point out that one of these places is right above Sri Lanka.
http://michaelsmith.id.au
Informative post but just one correction, at end of life the birds in geo RAISE their orbit. Decay takes so long that the graveyard orbits are stable over pretty much everyone's planning horizon (centuries+). If collisions occur up there then relative velocities are hopefully small enough to limit the debris field.
Rotovators are highly valuable and actually need to operate in LEO to throw things out of LEO, both up and down -- and Rotovators are quite vulnerable to debris.
Blah, blah, blah. Rotovators are "valuable" the same way unicorns and genies are "valuable", which is to say they are valuable in theory, but since we don't have any nor do we have any prospect of acquiring any anytime soon, it would be completely ridiculous to make expensive financial concessions based on this imaginary "value".
If a job's not worth doing, it's not worth doing right.
Rocks the size of these satellites enter earth's atmosphere all the time. Fortunately, we have an atmosphere that does a pretty good job of destroying most smaller objects that enter it. And humans only inhabit a tiny fraction of the earth's surface, so whatever does make it through the atmosphere usually lands in the ocean, or uninhabited areas.
Actually, any piece large enough to pose a threat to anything we care about can be tracked, and by what counts as ancient technology: the AN/FPS-85 phased array spacetrack radar, for example.
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ablation cascade
Media that can be recorded and distributed can be recorded and distributed.
-kfg
As much as you think it is, Planetes is a rather on-topic example for this story. It's not like he said, "Oh, remember that scene in Wall-E that was like this?" or some other vaguely-linked show, movie, or book.
Way to purposely confuse http://en.wikipedia.org/wiki/Micro- Meter with http://en.wikipedia.org/wiki/Micrometer
A garbage-collecting ship like the Toy Box is not likely to be feasible for anything other than the largest debris pieces. You would have to expend huge amounts of energy to match velocities with each little group of debris, and you wouldn't get much useful scrap from them. The wiki page you mention actually discusses this briefly.
Not to troll or to dwell into politics here, But does anyone here know any numbers for the *actual* chances/probabilities that satellite A will collide with satellite B in orbit around the Earth?
The chance is 1, that's given that your question has no time frame, hence I am assuming infinite time, over which every satalite in space would eventually crash if left to its own devices.
Blazing Spiders
http://en.wikipedia.org/wiki/Whipple_shield/
Small things won't necessarily damage a spacecraft although there's a limit to how much you can protect it and protection does increase the mass.
Space Mission Analysis and Design has tabulated some orbit life times. For high-ballistic coefficient satellites (high mass to drag ratio), some altitudes and lifetimes are:
100km: 0.06 days
450km (roughly ISS altitude): 2 years
1000km: 1 million years
above: no loss of altitude
Better to use a laser cannon, an ion cannon would just disable electronics. Sir, hand over your geek card please.
"Each satellite weighed well over 1,000 pounds"
Actually, their weight in space is pretty close to 0. Their mass is still relevant, and even more relevant is their velocity.
Catastrophic collision? Hmmm. Actually, that probably is about right. Even the ISS is pretty much guaranteed to be destroyed in a catastrophic collision within the next 5-10 years, and that's in a relatively safe place.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)