NASA's Fermi Spacecraft Dodged a Defunct Russian Satellite 47
g01d4 writes "On March 29, 2012, NASA scientists learned that the space agency's Fermi Gamma-ray Space Telescope was headed for a potential conjunction (close approach) with Cosmos 1805, a defunct Russian satellite from the Cold War era. The team knew that the only way to move Fermi would be to fire thrusters designed to move the spacecraft out of orbit at the end of its operating life. On April 3rd, shortly after noon EDT, the space agency fired all thrusters for one second. When it was over, everyone involved 'just sighed with relief that it all went well.' By 1 p.m., the spacecraft had returned to its mission."
Should we assume the delay... (Score:2)
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It was due to time dilation.
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Yes, to prevent this satellite from possibly turning into junk now, we are now committed to turning it into space-junk later, for our kids satellites to deal with.
In Soviet Russia.. (Score:1)
Satellite Dodge You!
Why avoid it? (Score:2)
Nuke it from orbit, it's the only way to be sure. Not to mention that it's already in orbit.
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Nuke it from orbit, it's the only way to be sure. Not to mention that it's already in orbit.
Nice idea... simple solution... but if we take this seriously (sorry, too early in the morning for my sense of humour to have woken up yet) the only problem with it is that any explosive method of dealing with orbiting debris just creates lots of small and tiny pieces of shrapnel, and traveling through a field of that crap at orbital velocities is not going to be the highlight of your day. Not a problem if you are in an M1 Abrams battle tank, but satellites do not have armour, except for shielding against t
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Nuke it from orbit, it's the only way to be sure. Not to mention that it's already in orbit.
Be careful. It might not be Cosmos at all. It might be IKON and it'll nuke you back.
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A pretty thing but not something to mess with.
cold war just got hot (Score:3)
this is clearly a premeditated act of war by the russians. I propose we attack Uzbekistan.
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I propose we attack Uzbekistan.
Why not attack Hawaii instead? The weather is nicer.
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That didn't work out so well for Japan.
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Meh. Why do all that attacking? If the weather is nice, why don't we just lie on the beach with little umbrella drinks?
That's the way the Terrorists Win!
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That's the way the Tourists Win!
FTFY
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this is clearly a premeditated act of war by the russians. I propose we attack Uzbekistan.
Thanks god that George W. isn't still in office... he probably would.
Bad headline (Score:2, Informative)
Re:Bad headline (Score:5, Informative)
Though Fermi was expected to miss Cosmos by several-hundred feet, NASA scientists knew from experience that forecasting spacecraft positions a week in advance isn’t an exact science. For example, Iridium 33 and Cosmos 2251 collided in 2009 even though they were predicted to miss each other by approximately 1,900 feet. This was the first known satellite-to-satellite collision.
Re:Bad headline (Score:5, Informative)
If there was any debris from the Cosmos (either directly from it, or from interactions with other junk or such) could be within that area.
Our radar is not good enough to make it safe enough to pass by that closely.
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700' is ridiculously close when you're going miles per second and the Earth's atmosphere is constantly changing, changing each object's orbits by similar amounts regularly due to drag.
Heck, if the RADAR producing the data has a couple of microseconds of jitter in it's clock, the propagation estimates could be off by that amount....Basically, 700' is pretty close to the noise of our estimations for orbital objects like this, and it's just better to be safe than sorry. Not to mention, who knows what small pi
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Except, you don't know the margin of error in either our knowledge of Fermi's orbit or that of Cosmos 1805's orbit. But I'd be willing to bet that the margins are large enough that a predicted 700' approach would place the two spheres of position sufficiently in overlap that there was a non-zero chance of collision.
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Actually, revised calculations made their pass even closer, within 30 milliseconds [csmonitor.com]. I may be doing the math wrong, but it seems like that's much closer, like an order of magnitude closer than 700' and then some.
Orbital Envoirment Protection Agency.... (Score:2, Interesting)
It seems to have reached a point where the amount of orbital garbage is causing major (and expensive) problems.
I think that if anyone puts a sat in orbit without dodging capability, they are fools, and potentially contributing to the 'littering' of orbitals.
It's past time to start working on and TESTING solutions to clean up the orbitals before it gets even more out of hand.
Or is this some Earthshade Anti-Warming scheme I missed hearing about?
Re:Orbital Envoirment Protection Agency.... (Score:5, Insightful)
Oh man, where do you start with this?
In LEO, orbiting debris are a self limiting problem. They will eventually deorbit on their own. So I guess that's not an issue for you.
In Geosynchronous orbit, every object is going to be pretty much moving in exactly the same direction anyway so the relative velocity is really small. The risk of collision is pretty small and the debris created would be minimal at low collision energies.
Outside these two areas, collecting orbiting debris, which vary in size from a few tons down to a few grams is a daunting task at best. How do one would imagine this could be done is the stuff of science fiction at best. Any collection system would by definition need to collect varying sized objects passing though a huge (by human standards) volume. This means there will need to be some pretty large structures launched, flown in space, survive the impact of collecting the desired objects and dispose of the collected mass. All this will need to happen without adding to the problem....
I just don't see how we are going to do this.
Personally, mankind would be better off if we took a debris mitigation strategy that required all launched hardware be mindful of not creating debris in orbits that would not naturally reenter within 5 years or so. We do this kind of thing now, at least the responsible people throwing most of the stuff in to space do, no telling what DPRK does.
Other than that, we might want to start thinking about building "space tugs" that can capture the junk that's collecting in geosynchronous orbit, tug it to less popular locations and work on ways to recycle parts of it. It sure doesn't seem worth the effort to deorbit the stuff that is that high up.
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Wouldn't altitude and velocities in geosynchronous orbit have to be exactly identical by definition? Otherwise it wouldn't be geosynchronous orbit and stuff would drift forward or backward.
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If you want to be pedantic, no. "Geosynchronous" means that it has a 1-day orbital period but does not specify the inclination or eccentricity of that orbit. The correct term for what you're talking about is "geostationary".
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The GP has a point. The GGP states they have little relative velocity, which means they would have to have the same inclination. A geosynchronous satellite that is moving in the opposite direction is going to have a ton of relative velocity and would have disastrous results in the event of a collision.
So perhaps the GPP meant geostationary (or close to it), not just geosyncronous (if the only definition of that is the satellite has a 1-day orbit). However, I am not an astrologer or any sort of scientist, so
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And exactly how do you propose this would work with lasers?
Two effects of lasers could be useful, but I don't think either of them really helps in any useful way.
One, you could push an object with a laser. The effect is pretty small, but you could adjust an object's orbit by giving it a small push from time to time. I suppose you could eventually get it to re-enter if you can adjust the orbit enough over time. This would take a LONG time considering you would likely want the laser to be earth based so yo
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A very, very large aerogel sponge. Getting the actual sponge to deorbit would be a bitch, but at least it'd be easy to track.
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Well, Yuri Gagarin is still flying and he has right of way...
(Legend has it that he didn't die in a plane crash in 1968 and is still in orbit.)
Potential conjunction? (Score:2)
So the conjunction was averted and didn't happen?
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So the conjunction was averted and didn't happen?
Yep, that means another 1000 years of Skeksis rule.
Yuri Gagarin (Score:2)
Curious that we aren't working on clearing junk (Score:1)
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