Two satellites collide in orbit

Spaceflight Now ^ | February 11, 2009 | WILLIAM HARWOOD

[Names Ash Housewares]

In an unprecedented space collision, a commercial Iridium communications satellite and a presumably defunct Russian Cosmos satellite ran into each other Tuesday above northern Siberia, creating a cloud of wreckage, officials said today.

The international space station does not appear to be threatened by the debris, they said, but it's not yet clear whether it poses a risk to any other military or civilian satellites.

"They collided at an altitude of 790 kilometers (491 miles) over northern Siberia Tuesday about noon Washington time," said Nicholas Johnson, NASA's chief scientist for orbital debris at the Johnson Space Center in Houston. "The U.S. space surveillance network detected a large number of debris from both objects."

One source said nearly 300 fragments were being tracked, but Johnson said it was not yet clear how much debris was generated.

"It's going to take a while," he said. "It's very, very difficult to discriminate all those objects when they're really close together. And so, over the next couple of days, we'll have a much better understanding. But it's at a minimum, I think we're talking many, many dozens, if not hundreds."

[evets]

[r9etb]

I'm surprised the Iridium managers didn't have a better handle on the potential for collision.

I'm pretty sure the NORAD folks (or whatever they're called now) would have been aware of the potential collision, and issued a warning to Iridium -- I think that's pretty standard, but it may require Iridium to "subscribe."

In any case, if Iridium got a warning, they had a couple of options: do nothing, or do something. The decision would be based on three things: how soon will the event occur (is there time to do a maneuver?); and how well-known is the orbit of the Russian-made object?; and how soon can NORAD compute a more precise orbit solution?

The latter situation is not that simple to address: the standard NORAD orbit solutions are necessarily fairly inaccurate -- it's a matter of getting sufficient tracking data for the object, in an enviroment where there are 8000+ other bodies competing for measurements.

So it's only when there's a potential close approach that the dedicated tracks and more precise orbit determination begins. Even so, the uncertainties can be significant.

So, again, Iridium has to base their decision to burn, on an assessment of the uncertainty in the NORAD orbit solution: do you go with the "big space" argument, and hope for a miss; or if you're not sure about the NORAD orbit, will doing a burn maybe make things worse rather than better? Or are you going to do a burn and get well away -- which means downtime and perhaps complicated commanding if the burn direction is retrograde (a real issue for Iridium).

After all that ... my guess is that Iridium knew about the close approach and decided to do nothing, in hopes that the collision would not occur.

999 times out of 1000, they'd have been right.

[Dr. Bogus Pachysandra]

But I said look here brother
Who you jiving with that cosmik debris?
Now who you jiving with that cosmik debris?

[Does so]

Some of this "Iridium" will fall to Earth—creating a fine layer of "Iridium".

;)

[Danae]

Hopefully Gravity will clean most of it up, and the atmosphere.... but large Chunks.... that could be a real problem to a major city.

[isom35]

reminds me of Nomad and Tanru.

[JRios1968]

All your bewb are belong to us

[paulycy]

Sounds like the Ruski’s had a successful killer satellite test to me..

Obama will leap into action banning all US satellites from space forever rendering us blind but having kept space from being militarized (at least by us).

[peace with honor]

ROTFL!!!!

[bgill]

Any idea which Iridium it was or where/date it was launched from? Any identifying info on the Rusky? I wanted to enter it into www.heavens-above.com to see where it happened.

[rwfromkansas]

It’s great how we use space as our personal trash can. I can’t imagine trying to miss all that junk up there.

[SoldierDad]

What? The Fed stimulus plan and the CA budget proposal? Must of depleted the ozone.

[CJ Wolf]

Or was it a defunct Russian satellite sold to the Iranians and launched a few days ago? hmmmmm

[FreepShop1]

How has this affected global Sat Phone service?

[bgill]

As time goes on, those debris will (come down) some over months, most over years and decades and as the big ones come down they’ll be tracked, we’ll see them and the worst-case scenario, we’ll just dodge them if we have to. It’s the small things you can’t see are the ones that can do you harm.”

It's all fun and games until a piece crashes through your roof.

http://oregonspacegrant.wordpress.com/2009/02/11/breaking-news-satellite-collision-over-siberia-on-february-10-2009

[plsvn]

After all that ... my guess is that Iridium knew about the close approach and decided to do nothing, in hopes that the collision would not occur.

Well thought out comments.

It sure would be interesting to eventually learn the decision process.

[bgill]

How has this affected global Sat Phone service?

More importantly, how has this affected geocaching?

[Doomonyou]

OK greenies. Time to jump on your environmental clean up high horse.

[messierhunter]

Ditto, could you PM me if you find out? I’ll do the same in return. I do ISS tracking and I’d love to get a picture of the debris through my scope.

[petitfour]

The question is whether it was intentional or not. Barry says no to weapons in space. There are already weapons in space. See story. Did Pooty-poot order a demo or did someone smarter than Barry? lol