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Hubble Repair Mission At Risk

MollyB writes "According to Wired, the recent collision of satellites may put the Atlantis shuttle mission to repair Hubble in the 'unacceptable risk' status: 'The spectacular collision between two satellites on Feb. 10 could make the shuttle mission to fix the Hubble Space Telescope too risky to attempt. Before the collision, space junk problems had already upped the Hubble mission's risk of a "catastrophic impact" beyond NASA's usual limits, Nature's Geoff Brumfiel reported today, and now the problem will be worse. Mark Matney, an orbital debris specialist at the Johnson Space Center in Houston, Texas told the publication that even before the collision, the risk of an impact was 1 in 185, which was "uncomfortably close to unacceptable levels" and the satellite collision "is only going to add on to that."'"

5 of 224 comments (clear)

  1. hmm. by apodyopsis · · Score: 5, Interesting

    we were discussing the debris problem at work over coffee the other day.

    we were trying to find solutions to it in our non-expert fashion.

    sadly the best we could come up with were:

    (1) putting a impact shield around spacecraft - but the kind of impact speeds we are talking about probably makes this uneconomical as the shield would need to be massive.
    (2) some kind of automated space cleaner that went around removing debris - but we had no idea how that could possibly work or be designed
    (3) vastly improved tracking capabilities so we could avoid the worst areas and steer around them
    (4) pre-emptive removal of dead satalites (no, not shooting them down from earth - attaching small moters to send them into the atmosphere) - maybe steering them into a declining orbit as the last thing they do before swithing them off
    (5) just abandoning the whole outer space game anyhow and using a vast fiber optic ring on the surface for communication needs

    there were probably other ideas that we came up with that I cannot remember, but this might get some comments/advice/derision.

    but we all agreed, this problem will only get worse. and choosing different orbit altitudes only delays confronting the issue - but might be cheaper in the short term.

    1. Re:hmm. by Cally · · Score: 4, Interesting

      Re (4), deorbiting (or parking) dead satellites - this already happens to some extent, if vehicles are still commandable at EOL and have enough delta-v in the tank to make it to a high parking orbit (or a de-orbit burn), that's usually done. I've also seen tethers mooted as a fuel-free EOL mechanism for deorbit (winch out a 20km cable which drags through the upper atmosphere and burns off enough velocity to make the sc re-enter and burn up.) Problem is that all this costs mass, which means money. There's also the problem that lots of debris isn't under any kind of command (chunks of upper stages, satellites that died in action, dropped screwdrivers, slag from old Iridiums and and so on.)

      --
      "None are more hopelessly enslaved than those who falsely believe they are free." -- Goethe
  2. Re:Soak up debris? by MichaelSmith · · Score: 4, Interesting

    The objects we want to take out of orbit are in a stable trajectory. If they collide with an object fired directly from the ground they will lose some velocity and move into a lower orbit. Low altitude orbits decay quickly because of drag from the atmosphere so these objects will quickly burn up.

    The object you fire from the ground to cause a collision will be shoved sideways a short distance. It can't go into orbit.

    Having thought about it for a bit I think the best thing to send up in the sounding rocket is a bottle of liquid nitrogen. It will form an expanding cloud at orbital altitude. Debris which fly through the cloud will lose some speed and their orbits will decay. Sounding rocket firings could be timed to minimise impact on operational spacecraft.

  3. Last paragraph is rubbish by Kupfernigk · · Score: 5, Interesting
    You don't understand the Theory of Evolution. There is NO "next logical step" for a species which develops intelligence, and there is NO reason why not colonising space makes us a "dead end branch". As the late, great Jay Gould has pointed out, the main form of life on Earth (by biomass and by effect on the planet) is now, and has been for a very long time, bacteria. Bacteria achieve great adaptability without intelligence. If we cannot achieve the same adaptability, then environmental changes may make us extinct. But the test of evolutionary success is simply continued, unthreatened existence, not some hypothetical extension of range. If we "nuke ourselves", we've failed. If we learn to live in our existing environment without making it unusable, and adapt to its changes, we've succeeded. The idea that we must colonise space to validate our existence is a religion, not science.

    Before the troll mods start up, please let me say I'm not objecting to exploring the Solar System in the slightest (in fact I think it's far more useful than the LHC). I am pointing out that your justification makes no scientific sense.

    --
    From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."
  4. Except that by Kupfernigk · · Score: 4, Interesting
    Will the inhabitants of those "off-world colonies" survive? We are far less likely to adapt to their conditions. The change of getting wiped out before sustainability is reached is rather high (look at the history of the colonisation of the Americas). Meanwhile, the amount of energy it takes to put even small payloads into orbit is enormous. We could easily reduce our planet to below sustainability in trying to create colonies, all of which would then fail for lack of resources. We've just done this to our economy by trying to make it expand too fast, so we have a track record.

    Research on Earth into dealing with external threats such as infalling asteroids or comets, dealing with diseases, dealing with our own inbuilt tendency to commit genocide, is far cheaper and more likely to pay dividends. Let's protect ourselves from disease and space rocks first, then we will be demonstrating our adaptability and survival skills. Running for the hills is monkey behavior, dealing with the predators may be what made us human in the first place. After all, we could realistically have a basic comet and asteroid shield by 2030.

    I repeat: the idea of space colonies is currently not even science fiction, it's religion. Which was my original point.

    --
    From scarped cliff or quarried stone she cries "A thousand types are gone, I care for nothing, no not one."