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Space Science

Collided Satellite Debris Coming Down? 155

Posted by kdawson
from the boom-crash dept.
Jamie found this Bad Astronomy blog on the many reports beginning about 7 hours ago of one or more fireballs in the sky across Texas. That blog's proprietor first doubted that the phenomena could be due to the satellites that collided in orbit last week, but later left the possibility open. The National Weather Service for Jackson, KY put out an announcement about possible explosions and earthquakes across the area and blamed the defunct satellites. "These pieces of debris have been causing sonic booms...resulting in the vibrations being felt by some residents...as well as flashes of light across the sky. The cloud of debris is likely the result of the recent in orbit collision of two satellites on Tuesday...February 10th when Kosmos 2251 crashed into Iridium 33." An Austin TV station has more reports.
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Collided Satellite Debris Coming Down?

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  • nice view (Score:4, Interesting)

    by Criliric (879949) <Shane.belaire@gmail.com> on Sunday February 15, 2009 @08:10PM (#26867399)
    now this would be a cool sight to see, i'm hoping nobody gets hurt from all of this
    • by MrNaz (730548) * on Sunday February 15, 2009 @09:05PM (#26867799) Homepage

      Troll? Why is that marked troll? He muses what an impressive show it must be an then expresses concern for his fellow man.

      Finally! Incontrovertible proof that the Slashdot moderators are secretly encouraging members to express their disdain and apathy towards their kin thus creating an antisocial and disjointed population which would increase their control over them and facilitate the establishment of their New Global Order! Wake up sheeple! The Slashdot mods are taking over!

      What? What do you mean I have to lower my morphine dose?

    • by eltaco (1311561) on Sunday February 15, 2009 @09:25PM (#26867951)
      Insightful? Why is that marked insightful? He muses what an impressive show it must be an then expresses concern for his fellow man.

      etc etc.
    • Re:nice view (Score:4, Informative)

      by Anonymous Coward on Sunday February 15, 2009 @09:45PM (#26868107)

      Getting hit by a meteorite is pretty unlikely. The only well documented case happened in 1954 [wikipedia.org], and it only resulted in a bruise.

      There are many times more natural meteorites than artificial ones, so it's unlikely that anyone will be hurt by space debris meteorites.

    • Re: (Score:3, Funny)

      by dkleinsc (563838)

      I'm thinking the appropriate response while watching it would be "Goodness gracious, great balls of fire!"

    • Just a thought... if this is a sign that the debris field is increasing, then maybe we ought to be getting our astronauts down from the ISS. We may not be able to, later, if the debris field gets large enough.

  • earthquakes? (Score:5, Insightful)

    by thermian (1267986) on Sunday February 15, 2009 @08:11PM (#26867409)

    From a few tons of colliding satellite? Seriously?

    Oh dear, someone doesn't have a well tuned sense of scale methinks.

    • by fyoder (857358) on Sunday February 15, 2009 @08:16PM (#26867447) Homepage Journal

      Shhh, it's really the end times, earthquakes and fireballs in the sky and all that, but they don't want to alarm anybody. At least until the dead all rise and walk again by which point it should be obvious what's going on.

      • by Bandman (86149) <bandman@ g m a i l . com> on Sunday February 15, 2009 @08:36PM (#26867599) Homepage

        So wait, there are going to be zombies?

        Finally!

        I mean..uhh..damn...yea...I'm not excited at all...

        /breaks out the cricket bat

        • Re: (Score:2, Funny)

          by galaxia26 (918378)
          Uhm... You've got red on you.
        • by Goffee71 (628501)
          Hmm, cricket bat or baseball bat? In the face of a zombie horde, who would do better, Brits or our American cousins?

          While I like the idea of the extra surface area of the cricket bat (more stopping power - assuming you hit them with the face), I think the baseball bat would have better melee appeal (better swinging power) as you could continue to swing more easily through the stroke after contact and you don't have to realign the bat for the next swing.

          Well, that's my Monday sorted - off to Umbrella
      • Re:earthquakes? (Score:4, Informative)

        by Laser_iCE (1125271) on Sunday February 15, 2009 @09:10PM (#26867841)
        Well, we were warned...

        ZOMBIES AHEAD! [oregonlive.com]
        • Re: (Score:1, Informative)

          by Anonymous Coward
          Holding "Control" and "Shift" on the roadsign control panel while typing in "DIPY" will reset the sign to the default access password, "DOTS".
      • by nizo (81281) * on Sunday February 15, 2009 @09:39PM (#26868063) Homepage Journal

        I'm such a moron for buying an electric chainsaw. I KNEW there was a reason I should have bought a gas one instead.

      • Re: (Score:1, Redundant)

        by evilviper (135110)

        At least until the dead all rise and walk again by which point it should be obvious what's going on.

        Nah. Just a pharmaceutical company testing a new drug... one which works even AFTER the disease has killed the individual.

        Move along.

      • by CTalkobt (81900) on Sunday February 15, 2009 @10:34PM (#26868477) Homepage

        Gah, not the rapture. My wife wants the stupid bathroom to be finished remodeling before anyone else makes alterations...

        Geesh... To hear her whine and complain about how long I've taken - I can just hear it now, "You waited so long the rapture occurred... "

        • by Lars T. (470328)

          Gah, not the rapture. My wife wants the stupid bathroom to be finished remodeling before anyone else makes alterations...

          Geesh... To hear her whine and complain about how long I've taken - I can just hear it now, "You waited so long the rapture occurred... "

          Just make sure she leads a good, Christian life (and you don't) - and you will never hear that from her.

      • by rastilin (752802)
        That is quite possibly the best quote I've read so far this month, mind if I use it as a sig?
      • I've been training for that all weekend ever since I purchased Left 4 Dead, the Army's Zombie murder simulator designed to train young soldiers to pull the trigger on a Z without hesitating.

      • Shhh, it's really the end times, earthquakes and fireballs in the sky and all that, but they don't want to alarm anybody. At least until the dead all rise and walk again by which point it should be obvious what's going on.

        Nobody steps on a church in my town!

      • Ooh, I'm really looking forward to the Rapture. The world will be so much more sane a place with all the religious nuts gone.

    • Re:earthquakes? (Score:5, Informative)

      by falken0905 (624713) on Sunday February 15, 2009 @08:20PM (#26867479)
      RTFA carefully. Citizens are reporting sounds and vibrations they -think- are earthquakes etc. but authorities are saying it is just caused by the sonic booms of stuff (whatever it is) entering the atmosphere and exploding.
      • Re: (Score:3, Informative)

        by dougisfunny (1200171)

        Giant subterranean worms moving through the bedrock, and they cover it up.

        It's the only explanation.

      • by db32 (862117)
        I'm glad you said this as I was about to. There have been some pretty amusing stories of people reporting sonic booms as other things. From what I gather there were more than a few frantic calls about Russian attacks during the earlier days of super sonic aircraft since people thought there were bombs going off somewhere.
    • Re:earthquakes? (Score:5, Informative)

      by SpazmodeusG (1334705) on Sunday February 15, 2009 @08:20PM (#26867481)
      Seismometers detect things like sonic booms and lightning strikes from quite large distances away.
      So if it created a sonic boom coming down through the atmosphere it could have been detected as seismic activity.
      • by vikstar (615372)

        so it's not really an earthquake, more like an airquake.

      • Seismometers detect things like sonic booms and lightning strikes from quite large distances away.

        So if it created a sonic boom coming down through the atmosphere it could have been detected as seismic activity.

        Detect, yes, but in a different way. Your ears can detect both cars and hummingbirds, but you have no problem differentiating between the two. The seismometers also detect the sonic booms, but they know that it's not seismic activity.

    • =(1/2)mv^2

      If you're near a couple of tons at reentry speed, yeah. I'll bet you'd think it was an earthquake too.

      • Re:Kv (Score:4, Interesting)

        by c6gunner (950153) on Monday February 16, 2009 @02:19AM (#26869777)

        If you're near a couple of tons at reentry speed, yeah. I'll bet you'd think it was an earthquake too.

        Except that none of the pieces would be anywhere NEAR that size. The iridium satellite was about half a ton, and the Russian satellite weighed in at just under a ton. Even if they had fused into one solid mass on impact, you still wouldn't have enough material to make up "a couple of tons".

        • It's not the mass that's the important part. An increase in mass results in a linear increase in kinetic energy. Double the mass? Double the kinetic energy.

          It's velocity that's the problem. That term is squared. Double the velocity and you get 4x the energy on impact.

          So even a few pounds moving quick enough will make an impressive kaboom. And these satellites weigh in the neighborhood of a ton or so.

          So I still stand by it - this would make impressive impacts, easily confused with earthquakes I'm

          • Re: (Score:3, Insightful)

            by c6gunner (950153)

            It's velocity that's the problem. That term is squared. Double the velocity and you get 4x the energy on impact.

            Well, sure, if you're lobbing satellite parts at the moon. The earth has an atmosphere, though. Air resistance doesn't scale linearly. The faster your initial velocity, the greater your loss of velocity due to air resistance. At very high velocities, air resistance increases exponentially. Therefore, double the velocity on de-orbit does not mean double the impact velocity.

            It's not the mass th

    • Re:earthquakes? (Score:4, Interesting)

      by andy_t_roo (912592) on Monday February 16, 2009 @12:03AM (#26869045)

      yep - just a little overrated.
      Objects in low earth orbit have 32.1 to 38.6 MJ/kg [wikipedia.org] energy. Assuming that the collision between 2 1000kg satellites leaves 1/2 the energy left over, there's potentially 3.8e10J of energy. 1g of TNT is defined as 4184J [wikipedia.org] therefore the left over energy is equal to 9.2T of tnt, minus what is lost as objects pass through the atmosphere, what was used to break the satellite up, etc...

      To put this into scale, if all this energy was to go off at one point in an earthquake, to cause the rumblings in TFA, it would be around mangitude 2.7 [wikipedia.org] or so, of which there are about a thousand per day and are generally not felt.

      This is discounting that the satellite broke into quite a few pieces which will gradually enter the atmosphere over the next while.

    • by nedlohs (1335013)

      Because no one could mistake a sonic boom from a piece of space job speeding through the atmosphere for an earthquake.

      We are talking about people who call the national weather service to report such a thing, rather than say the USGS. That they would interpret something they have never experienced before incorrectly doesn't seem strange, to me at least.

    • by ultranova (717540)

      From a few tons of colliding satellite? Seriously?

      Well, a passing truck causes the ground to vibrate, which is technically an earthquake, for some definitions of earthquake. For that matter, an ant crawling causes a tiny earthquake every time it lowers one of its legs.

      Oh dear, someone doesn't have a well tuned sense of scale methinks.

      Luckily, any mistake can be corrected by liberal use of pedantry and redefinition of words ;).

  • by bitcastle (934210) on Sunday February 15, 2009 @08:12PM (#26867417) Homepage
    "I can now state unequivocally that this is not the result of the satellite collision. The meteor is moving far too quickly for that; satellite collision debris would fall at perhaps 10 km/sec max, while incoming meteoroids are moving at 11km/sec at a minimum, and this thing is screaming across the sky at several dozen km/sec (assuming itâ(TM)s at a typical meteor height of 50 or more km). So I was probably right in the first place, and what we have here is almost certainly a single object, perhaps a meter or two across, and it came from deep space"
  • it figures... (Score:1, Interesting)

    by yodleboy (982200)
    just like columbia, i slept through the whole thing. need to come up with a business plan for notifying people in the event of space debris showers...
  • by Keramos (1263560) on Sunday February 15, 2009 @08:15PM (#26867435)
    My understanding was that the satellites were in an orbit high enough that the debris would float around for several thousand years before being caught by the atmosphere. I suppose a few bits might have had the energy to move closer in, but all in all it sounds more like the Martians have arrived. Might be a good idea to go make some bacteria bombs before they finish building those tripedal walkers.
    • by EmbeddedJanitor (597831) on Sunday February 15, 2009 @08:24PM (#26867507)
      Staying in orbit requires a the right velocity. The results of a collision will have different velocities and some of that will de-orbit.
      • by bcwright (871193) on Sunday February 15, 2009 @09:23PM (#26867931)

        This is obviously true, but it usually takes a while for debris to de-orbit especially if it's not in very low orbit (where it will encounter more atmospheric drag). Offhand the only way I see for this to be likely to happen so quickly would be if the satellites had been moving in opposite directions (a head-on collision, in other words) - that ought to result in at least some debris having a markedly different orbital energy from that of either of the two satellites before the collision. But most satellites orbit in either an easterly direction (it takes less energy to launch them in that direction because you get an energy boost from the Earth's rotation) or in a polar orbit (which is useful because even though it requires more energy the satellite can pass over all of the Earth's surface) - so head-on collisions are relatively unlikely.

        • by cathector (972646)

          agreed that the variance in outgoing velocities will be maximal when the bodies have a head-on collision and minimal when they have a "collision" while moving nearly parallel. so these two bodies were moving more or less perpendicularly [spaceweather.com], which to me leaves plenty of room for specular collision to produce debris heading straight down. think of how the velocities of two billiard balls can be wildly different from their velocities before collision, all the while maintaining the total momentum of the system.

          • by bcwright (871193)
            There might well be some fragments heading "straight down" (as you put it) - but that would mean that other pieces would need to be kicked into a higher orbit in order to conserve momentum. Probably most of the debris cloud would remain at approximately the same altitude but in a somewhat different orbit. Most small orbital objects (on the order of a few grams or less) reentering the atmosphere just don't produce much of a display; you need more mass - a whole intact satellite, for example. I just don
        • What about the bits which flew in to the earth, or at that kind of angle as opposed to out in to space.

          Its not like they collide and all the debris magically flies away from the earth.
          A awful lot would go downwards, while some would go away.

        • by sjames (1099) on Sunday February 15, 2009 @11:27PM (#26868853) Homepage

          A head on collision IS extremely unlikely, which is why you can have some parts re-enter so soon. Imagine a glancing collision where one satellite strikes the upper half of the other. The result can be a highly eccentric path that intersects the atmosphere. An additional factor could be if a pressurization tank bursts in the collision.

        • I don't have the link handy, but there was a gif posted in the original article about the collision which showed that the satellites were traveling roughly orthogonally to each other.
        • by Thaelon (250687)

          IIRC, the animated collision .gif I viewed on the last slashdot story showed them colliding at approximately right angles. And since they're satellites they were probably maintaining a constant altitude. Given that they collided, they had to be in the same altitude. Given the same altitude, and being satellites you can reasonably conclude that they had the same velocity.

          Given this information, I would imagine the collision this would send debris in all kinds of directions with the center of mass moving off

      • by PhilHibbs (4537)

        Staying in orbit also requires that there be no air resistance from the atmosphere. At the 700km or so that they were orbiting, the resistance would naturally bring it down in a couple of years. Fragments from the impact were probably sent off in all directions, but I have no idea whether the larger chunks would tend to continue in much the same orbit or be wildly deflected. Any significant deflection should bring the pieces down a lot faster.

    • by QuantumG (50515) *

      They were in a 667km orbit. That's the low end of LEO.

      • by bcwright (871193) on Sunday February 15, 2009 @09:06PM (#26867803)

        That's far from the lowest LEO. The International Space Station (ISS) orbits at about 358km.

        • by QuantumG (50515) * <qg@biodome.org> on Sunday February 15, 2009 @09:13PM (#26867863) Homepage Journal

          LEO is between 160 and 2000 km.. therefore 600 is in the low end of LEO.

          • by bcwright (871193)
            It's still high enough that it's unlikely that significant debris from the collision could de-orbit that quickly - which was the point. A few miscellaneous chunks of debris would not make a trail visible from the ground - you'd need a significant mass in a single chunk or at least in a cloud that all de-orbited together.
            • by ultranova (717540)

              It's still high enough that it's unlikely that significant debris from the collision could de-orbit that quickly - which was the point.

              If two satellites collide in orbit and turn into an expanding cloud of debris, then a significant part of that debris - a bit under half, actually - is going to hit the Earth soon, on the account of expanding into the atmosphere. The part of the cloud expanding backwards relative to the direction of the orbit is also going to at least lower its orbit if not fall outright, s

          • LEO is between 160 and 2000 km.. therefore 600 is in the low end of LEO.

            I disagree. When dealing with values that have such huge ranges, and get really interesting at the small values, it is better to think in logarithmic terms, and on that basis, 600 is squarely in the middle.

            Anyway, you're just picking a fight. Most of the really interesting LEO stuff is below 600. Manned spaceflight, Hubble, etc.

            (not to say I don't usually enjoy the fights you pick! :) )

    • by Narpak (961733)

      Might be a good idea to go make some bacteria bombs before they finish building those tripedal walkers.

      Check. I'll go down to the local kindergarten and start collection specimens; you begin assembling the deliver mechanism (though I reckon just holding up a kid a making it sneeze should do the trick).

    • Until someone tells me why it would not be the case, I would expect the initial vectors of the debris to form the usual cone shape of ballistic collisions. That being so, it is quite possible that a portion of that cone would hit the atmosphere fairly quickly.

      The people who fuss about satellites don't care about that portion, they tend to focus on the rest of the spatter cone, since that is what is going to be a long term risk to their satellites.

  • As someone noted above, I'm now very sure this was a natural piece of cosmic debris, a chunk of asteroid or something similar. I posted a wrapup with my thoughts [discovermagazine.com].
  • First wave (Score:1, Redundant)

    by nurb432 (527695)

    They are coming.. Good thing we had secret killer satellites to shoot down the alien's ships.

  • by daemonburrito (1026186) on Sunday February 15, 2009 @08:27PM (#26867525) Journal

    The FAA issued a Notice To Airmen yesterday predicting debris and asking pilots to report.

    I think there may be some conflict between the FAA's safety concerns and NORAD's secrecy. NORAD will weigh in eventually (when they're sure what they can and can't say), but there no reason to throw away the FAA's opinion, even though they are not the "go to" agency.

    • by mail2345 (1201389)
      All they find is Santa returning from a strip club...
    • There's no sense in trying to keep secret data that anyone with binoculars can track. The military satellites, those that can read your licence plates, are so big and in low orbit that many people and organizations around the world keep track of them.
      You can find that data from independent sites in the internet and try to watch if you can spot them.

      The NORAD tracking data on both active satellites and debris is listed here [celestrak.com].

  • There is no mention of "possible explosions" in the original article. The debris has also not been "blamed" for earthquakes, but it says that people may have mistaken the the phenomenon for them.
    • by Anonymous Coward

      The debris has also not been "blamed" for earthquakes, but it says that people may have mistaken the the phenomenon for them.

      These days I expect many Americans are not familiar with the sonic boom, likewise earthquakes. I know I don't have much familiarity with them myself.

      The only earthquake I ever knowingly felt was in south-east Indiana in '87 or '88 in the New Madrid fault zone. The house shifted for a split second or so. I felt the displacement and saw the water in the toilet sloshing.

      The only sonic boom I can personally recall hearing is from the shuttle Columbia breakup. I was inside my house north of Dallas and even s

  • helmets (Score:2, Funny)

    by Anonymous Coward

    Will the FSF be marketing an official helmet to protect against sat debris, assuming their tinfoil hats would be sadly insufficient against this new vector?

  • http://www.news8austin.com/content/top_stories/default.asp?ArID=232081 [news8austin.com] Halfway down the page, video titled "sky is falling". Also, slow-mo footage of runners highlights bounciness.
  • The sky is falling! (Score:2, Interesting)

    by defiek (1478245)
    It can only stay up there so long. I read somewhere that they estimated a bulk of the debris will stay in orbit for 10,000 years.
  • A while ago I saw a google earth version of all the satellites in orbit, and I had no idea there were so many. If even 25% of them are dead, I think it would be great if they came down. I'm surprised anyone can get a space ship through that.

    • Re: (Score:3, Funny)

      by FireFury03 (653718)

      Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space.

    • A while ago I saw a google earth version of all the satellites in orbit, and I had no idea there were so many. If even 25% of them are dead, I think it would be great if they came down.

      Here's your broom and dustpan. Welcome to Hell, now get to work...

  • What happened to all the alarmist articles saying that this space debris was going to be up there for 10,000 years?

    It sounded like BS when I read it, now that pieces are coming down it only confirms my suspicions.

    • Re: (Score:1, Interesting)

      by Anonymous Coward

      Debris thrown into a higher orbit will last almost indefinitely orbits greater than 1,000km have lifetimes of thousands of years. Debris that is accelerated into a lower orbit has lifespans of day to months, anything less than 100km will last less than a year.

      I was interviewed by lex18 news about this yesterday, I work with the 21m space tracking system at Morehead State University, and have been studying orbital mechanics in advance of the launch of our cubesat KYSAT1

    • Well two things.

      1) If you have ever seen an explosion your BS-o-meter should have alerted you to the fact that some debris would go into a HIGHER orbit... and some would go into a LOWER orbit. Therefore you can have material re-enter the atmosphere AND stay in orbit for thousands of years.

      2) It's not the sattelite debris. It's a coincidence and your suspicions aren't confirmed... and they're wrong.

      Since when has basic newtonian physics been "alarmist"?

  • by Viadd (173388) on Monday February 16, 2009 @12:06AM (#26869063)

    (Also posted to Bad Astronomy.)

    A simple orbital analysis using the ground tracks from, e.g. Heavens-Above.com shows that this was not debris form the collision.

    The debris from a collision keeps more or less the same orbit as before, but is spread out along the orbit. (Orbital plane changes require a lot more delta-v than changing the along-track position or altitude, since drift along the orbit accumulates, but displacements across the orbit swing back and forth with each cycle.)

    Looking at the ground tracks of
    Iridium 33 [heavens-above.com] and
    Cosmos 2251 [heavens-above.com]

    Just eyeballing the tracks, the North-going leg of the orbit of Iridium 33 crosses the latitude of Texas at around 10 PM local time. For Cosmos 2251, it crosses about 4 PM local.

    An 11 AM fireball could be Iridium debris, but only if it were heading to the south-south-east. The fireball was heading NNE. So this was NOT debris from either satellite.

  • Now if only...instead of crashing Kosmos 2251 or Iridium 33 they could have crashed say Plutonium 239,
    then we would be in business!

  • the result of the recent in orbit collision of two satellites on Tuesday...February 10th when Kosmos 2251 crashed into Iridium 33

    Producing Ufonium 2284 ?

  • The satellite
    Was out of sight
    Radioactive though
    It was all right
    When it was high
    But now its very low...
  • I saw a a large fireball, which I assumed to just be a meteor on my way from State College to York last night. Could that be bits of it? Funny. First 'falling star' I've ever seen, and it was a big'un!

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