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Exploding Robots May Scout Hazardous Asteroids

An anonymous reader writes to mention NewScientist is reporting that a small force of robots designed to explode could help reveal an asteroid's inner structure. This could in turn allow scientists a better understanding of how to divert a rogue asteroid on a collision course with Earth. From the article: "The main spacecraft would stay a few dozen kilometers away, perhaps nudging the probes towards the asteroid using springs. Once on the surface, the protective spherical shell of each probe would open to allow the probe to scan the surface nearby. To reduce complexity and costs, the probes lack solar panels and run on battery power, limiting their lifetime to a few days. But each probe could still cover a lot of ground in that time, as they could be fitted with small thrusters to let them hop across the surface. Eventually the probes could detonate onboard explosives, sacrificing themselves for science one by one. Probes that had not yet detonated would listen for any seismic waves sent rippling out from the explosion, and the main spacecraft could observe the craters left behind. That would tell scientists about the asteroid's strength and internal structure."

120 comments

  1. Smells of... by Tablizer · · Score: 2, Funny

    Exploration by destruction. If that is not a Bush Administration approach to space exploration, I don't know what is :-)

    1. Re:Smells of... by __aaclcg7560 · · Score: 2, Funny

      Funny... I thought Sony found a new market for their exploding laptop batteries.

    2. Re:Smells of... by Anonymous Coward · · Score: 0

      "Redundant"? I challenge you to point to a previous post with the same.

    3. Re:Smells of... by SteveO6385 · · Score: 1

      Quiet you fool, you keep it up and the State of the Union will be filled with "If we don't destroy those meteors, then the terrorists have won".

      Hell, all we really have to do is scare away these things. Think of it: if we turn our satellites up towards the impending rock of doom, and broadcast our horrible earth waves to it, it'll run in fear. It's not gonna take long until it can't stand being transmitted Windows Updates in it's general direction before it turns and warns the rest of the galaxy to evade our planet.

      .....or gang up on us and destroy the source in Redman. :P

  2. No wonder they're hazardous! by spun · · Score: 4, Funny

    What with all the exploding robots exploring them, of course they're going to be a bit hazardous.

    --
    - None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
    1. Re:No wonder they're hazardous! by Anonymous Coward · · Score: 0

      Will this alter the trajectory of them and cause earth to be in harms way?

    2. Re:No wonder they're hazardous! by eviloverlordx · · Score: 5, Funny

      What with all the exploding robots exploring them, of course they're going to be a bit hazardous.

      I would hate to be one of the engineers testing these.

      --
      'Loose' is when your pants are three sizes too big. 'Lose' is when you misuse 'loose'.
    3. Re:No wonder they're hazardous! by Tackhead · · Score: 1
      > > What with all the exploding robots exploring them, of course they're going to be a bit hazardous.
      >
      > I would hate to be one of the engineers testing these.

      "Engineers? What about the poor robots?"
      - PETRO: People for the Ethical Treatment of Robot Overlords

    4. Re:No wonder they're hazardous! by Howserx · · Score: 1

      WTF! where are all the jokes about them being powered by dell batteries? Maybe I should threshold at less then 3...

      --
      I support the troops. I pay f'ing taxes.
    5. Re:No wonder they're hazardous! by cayenne8 · · Score: 3, Funny
      "Will this alter the trajectory of them and cause earth to be in harms way?"

      I think the bigger worry would be:

      I hope to hell OTHER planets aren't coming up with exploding robot probes....and aming them at that 'earth' planet way out there....to see what kind of seismic activity they can detect.

      --
      Light travels faster than sound. This is why some people appear bright until you hear them speak.........
    6. Re:No wonder they're hazardous! by Venerable+Vegetable · · Score: 1

      Brings the saying "defective by design" to a whole new level.

    7. Re:No wonder they're hazardous! by ray-auch · · Score: 1

      With all the exploding we do all by ourselves on this planet I'd be suprised if we noticed.

      On the other hand... Tunguska...

    8. Re:No wonder they're hazardous! by Anonymous Coward · · Score: 0

      Shouldn't it rather be destructive by design?

  3. Robots by Van+Cutter+Romney · · Score: 0

    Why do we need robots when we have Bruce Willis to do the job?

    --
    Help a man when he is in trouble and he will remember you when he is in trouble again.
    1. Re:Robots by rhyder128k · · Score: 1

      These robots are going to need a considerable degree of in-built intelligence. So, quite different.

      --
      Michael Reed, freelance tech writer.
  4. Think of the Asteroids by Suffering+Bastard · · Score: 5, Funny

    Oh great, we're about to start pissing off asteroids by blowing up their kin. OF COURSE they're going to come falling on us, if for no other reason than retaliation.

    Watch for attacking asteroid clusters, armed to the teeth with lasers and nuclear bombs!

    ha ha, just kidding...asteroids don't have teeth.

    --
    "Molest me not with this pocket calculator stuff."
    - Deep Thought
    1. Re:Think of the Asteroids by OctaviusIII · · Score: 1

      Looks like NASA is getting into the habit of blowing up its enemies, too. It'll be just like Iraq all over again!

      --
      What's this? Another weblog? On transit?
    2. Re:Think of the Asteroids by Anonymous Coward · · Score: 0

      Oh great, we're about to start pissing off asteroids by blowing up their kin. OF COURSE they're going to come falling on us, if for no other reason than retaliation.

      When fighting asteroids you just make more asteroids. You can not win a war on asteroids.

  5. I for one... by guruevi · · Score: 0, Redundant

    welcome our new asteroid-hopping self-destructive explorer robots. I hope they asplode before they turn against us.

    --
    Custom electronics and digital signage for your business: www.evcircuits.com
    1. Re:I for one... by Tablizer · · Score: 3, Funny

      I for one welcome these expl [NO CARRIER]

    2. Re:I for one... by Anonymous Coward · · Score: 0

      Jeeeeez, Bill "Tard" Gates starts his hype machine about robots in an effort to pump up Micro$oft stock and now everyone uses the term robot for everything.

      Robots are the new nano!

    3. Re:I for one... by Tablizer · · Score: 1

      I hope they asplode

      asplode? Freudian slip from one who does not like Microsoft web tools? "Assplode" is for goatse haters.

  6. Bomb #20 says... by Half+a+dent · · Score: 4, Funny

    "Let there be light"

    1. Re:Bomb #20 says... by drinkypoo · · Score: 1

      To save some of you from googling: linky

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
  7. Attention: by Professr3 · · Score: 1
    OMG ROLLERMINES

    that is all.

  8. Great PR by 4solarisinfo · · Score: 1

    Actually, I bet this is going to give them some really good PR. Sound science, new territory, and explosions.

    The so-called 'news' people may actually run a story like this, getting average people into space again, which has done so much for scientific research as a whole.

    Now, what celebrity could we also send there.... and blow up?

  9. Deep Impact was on TV last week by davidwr · · Score: 1

    In Deep Impact NASA sent a manned mission to nuke a killer comet.

    Sounds like a perfect job for robots.

    --
    Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
    1. Re:Deep Impact was on TV last week by ray-auch · · Score: 1

      I think you missed the bit about it being a film.

      Robots are distinctly non-perfect for that. Consider the diaglogue:

      90mins of "beep... beep.... beep...." followed by "bang".

      Except you don't even get to hear that because the robot ship doesn't need any air in which to make a sound...

      I suppose you could focus on the ground action - 90mins of some guy pacing backwards and fowards muttering "metric, imperial, metric, imperial, fuck which was it?...".

  10. This technology was first used... by Anonymous Coward · · Score: 0

    ...on intestinal polyps found during colonoscopies, but the high death rate make it economically infeasible in that application.

  11. In a related story..... by ReidMaynard · · Score: 5, Funny

    NASA announces the hiring of Wile E. Coyote to a Senior Staff position....

    --
    -- www.globaltics.net

    Political discussion for a new world

  12. Re:I for one welcome our new exploding robots by WillAffleckUW · · Score: 1

    and thank the Gods that my space suit is armored.

    --
    -- Tigger warning: This post may contain tiggers! --
  13. warning: humor follows by zappepcs · · Score: 2, Funny

    Will these explorer androids be launched by the JSA? Jihad Space Agency?

    1. Re:warning: humor follows by Falkkin · · Score: 1

      -1, humor not appreciated

    2. Re:warning: humor follows by Anonymous Coward · · Score: 0

      something is wrong with your subject line

    3. Re:warning: humor follows by madcow_bg · · Score: 1

      ... in a galaxy far, far away.

      From your post, at least.

  14. 'Small and Cheap' by Normal+Dan · · Score: 2, Interesting

    Sometimes I wonder what they mean by cheap. I suppose they mean cheap in comparison to other robots they could send. Either way, I do find this a bit exciting. It might lead to some interesting discoveries. Who knows, we could soon by mining these asteroids some day and all these experiments will pay for themselves. Then again, with all the budget cuts NASA has been taking these days, I wonder if these small and cheap robots will even get off the ground. I suppose only time will tell.

    --
    A unique way to learn a language: http://languageloom.com
  15. This just in..... by ReidMaynard · · Score: 2, Funny

    New Space robots look amazing like a 1972 Ford Pinto ...

    --
    -- www.globaltics.net

    Political discussion for a new world

  16. Last words from the robots: by UnknowingFool · · Score: 4, Funny

    "I think you ought to know I'm feeling very depressed."

    --
    Well, there's spam egg sausage and spam, that's not got much spam in it.
    1. Re:Last words from the robots: by LandKurt · · Score: 1

      "Let there be light." (Bomb #20 - Dark Star)

  17. Aliens! by endianx · · Score: 1

    "Aliens attacked earth today after encountering our army of exploding robots and interpreting them as an act of war. News at 10."

    1. Re:Aliens! by bruce_the_loon · · Score: 1

      It's Film at 10, you ignorant fool!

      --
      Trying to become famous by taking photos. Visit my homepage please.
  18. Obligatory by Schraegstrichpunkt · · Score: 2, Funny

    Bite my shiny metal ass!

  19. Easy Economics: Capital vs Labor by Not_Wiggins · · Score: 3, Funny

    With the proliferation of people willing to strap bombs to their chests in order to "make the world better," it would certainly be easier (and cheaper) to recruit people who already know how to walk to a location and self-detonate than to spend it on "high tech" solutions.

    I can see the ad campaign now:

    "Tired of being labeled a terrorist? Why not join the new Space Explorers Club and really help humanity! Visitation with Allah guaranteed after mission! Sign up today!"

    Then research funds could be freed up to build robotic solutions the world REALLY want... sex bots! Woo!

    (For the humor impaired, insert tongue into cheek and re-read. ;) )

    --
    Diplomacy is the art of saying, "Nice doggie!" until you can find a rock.
  20. Exploding Robots? by ackthpt · · Score: 1

    This is a job for Agatha Hetrodyne

    --

    A feeling of having made the same mistake before: Deja Foobar
  21. Explosions? Quagmire! by Prysorra · · Score: 1

    Call it a quagmire and the media will be all over it....

    Any PR = good PR.

  22. Nothing new by Anonymous Coward · · Score: 0

    Insurgents in Iraq have been using these for years

  23. ObPython by sparcnut · · Score: 0

    The robot on top of your asteroid will now explode.

    *boom*

    --
    perl -e 'print $i=pack(c5, (41*2), sqrt(7056), (unpack(c,H)-2), oct(115), 10);'
  24. Gandalf quotation by LeDopore · · Score: 1

    He who breaks a thing to find out what it is has left the path of wisdom.

    --
    Expected time to finish is 1 hour and 60 minutes.
    1. Re:Gandalf quotation by d3ac0n · · Score: 1

      Gandalf was obviously NOT a geek.

      --
      Official Heretic from the "Church of Global Warming". Proven right thanks to whistle blowers. AGW = Flat Earth Theory
    2. Re:Gandalf quotation by Anonymous Coward · · Score: 0
      Gandalf quotation: He who breaks a thing to find out what it is has left the path of wisdom.


      You are correct. We should always base our highest technology research on the advice of a fictional character.
    3. Re:Gandalf quotation by camperdave · · Score: 2, Insightful

      If the advice is sound, what difference does it make if it came from a fictional character. When Yoda says, "Do, or do not. There is no 'try.'", is it somehow less valid because it came out of the mouth of a glorified sock puppet? When the fictional Captain Jean-Luc Picard says,"With the first link, the chain is forged. The first speech censored, the first thought forbidden, the first freedom denied, chains us all irrevocably." (incidentally, quoting another fictional character) does that mean that we are not chained when a thought is forbidden or a freedom denied?

      --
      When our name is on the back of your car, we're behind you all the way!
    4. Re:Gandalf quotation by Tim+C · · Score: 1

      The problem, such as it is, is that a lot of people listen more to who is being quoted than the quote itself. That is, it's not what's being said so much as who is saying it that lends the words their weight - it's an appeal to authority. Fictional characters are often imbued with an authority that they simply do not have; yes, Gandalf and Yoda are wise, but what they actually say is only as wise (or not) as their writers are.

      A lot of people have a tendency to hear/read a quotation and think "Oh, *X* said it? It must be true, they're clever/wise/good/etc!", and so react badly to a quotation from a fictional character. Just think of all the times you've seen a poster here bolster their argument by mentioning a couple of people who also support their point, even though they have no connection with the subject at hand (eg Linus's thoughts on DRM or copyright - he's a talented programmer, but he's not a lawyer).

  25. Hey Baby, by Anonymous Coward · · Score: 1, Funny

    I build exploding space robots for a living.
    Now there's a pickup line...

  26. Stupid Plan by Anonymous Coward · · Score: 1, Interesting

    If you are making robots capable of moving around and blowing up, why not make them lay the explosive and then back away to a safe spot? The robot could lay multiple bombs and never be destroyed. Why throw away good robotics?

    1. Re:Stupid Plan by Normal+Dan · · Score: 1

      You could drop a bomb then run away, but you would soon run out of power and have a useless robot anyway. If you really want to save the robot, you would need to add solar panels. You would also have to include a mechanism for dropping the bombs. You would also need to redesign the robots to withstand the wear and tear of space. Then you must think about the scientific benefit of having a robot on an asteroid you've already studied. In the end, it's far cheaper and efficient to just build and exploding robot.

      --
      A unique way to learn a language: http://languageloom.com
  27. Armageddon by writerjosh · · Score: 3, Funny

    Send Bruce Willis and Ben Affleck up there again. They're cheap and expendable. Plus they're not doing any good down here.

  28. As long as the probe survives. by IMarvinTPA · · Score: 1

    I just hope the probes can reach the surface of the comet at all.
    It may unexpectedly detonate before it even reaches the surface.

    IMarv

  29. oh yes! by el_coyotexdk · · Score: 1

    Robot Lemmings!

    1. Re:oh yes! by HTH+NE1 · · Score: 1
      Robot Lemmings!
      Bomberdroid!
      --
      Oh, say does that Star-Spangled Banner entwine / The myrtle of Venus with Bacchus's vine?
  30. robot conversation by planckscale · · Score: 1
    BOOOOM!

    Beezbot. This is Robot 35. Robot W34 detonated - Boop beep bop. Composition of asteroid is rock

    This is Commander Robot. Robot W35 please detonate

    This is W35. Why?

    This is Commander Robot. We need to determine composition of asteroid

    BOOOOM!

    Beezbot. This is Robot 36. Robot W35 detonated - Boop beep bop. Composition of asteroid is rock

    ...

    --
    Namaste
  31. Where to send resume... by Quiet_Desperation · · Score: 1

    Remote control sharks or exploding robots... remote control sharks... exploding robots... Argh!

  32. Re:Why are we not Performing Collisions? by xeromist · · Score: 1

    If we could easily push asteroids into a planet why not just push them away when they approach Earth?

    --
    This sig is exactly seventy characters long and a real waste of space!
  33. Virgin robots? by A+nonymous+Coward · · Score: 2, Funny

    Are the suicidal robots being misinformed about 72 virgin robots awaiting them?

    1. Re:Virgin robots? by MousePotato · · Score: 1

      Are the suicidal robots being misinformed about 72 virgin robots awaiting them? no, but, can you imagine the new nasa press releases;

      KSC, FLORIDA - In a bold initiative against rogue asteroids ordered by the Bush administration, NASA engineers have announced today that 3 asteroid probes have suceesfully completed their martydom operations. Each probe's sacrifice against the Trojans has brought the jihad to new levels and liberated us from the threat of these wandering interstellar crusaders in a series of pre-emptive strikes designed to provide security to the American peoples and bring democracy to peoples of the world.

    2. Re:Virgin robots? by Anonymous Coward · · Score: 0

      Oh, and can you prove that Robot Heaven doesn't have 72 virgin sex-bots for every robot martyr? Now there's a Futurama episode they'll never air on TV.

  34. We used to call those "missles" by James+McP · · Score: 1

    All funnin' aside, this does advance science quite a bit. I'm happy to see the "science bombs" properly specced out as disposable tech rather than the live-forever approach NASA typically produces (Go rovers!)

    Plus, I'm all for having an OTS weapon system for targets within the solar system. But I blame that on my recent reading list. Curse you John Ringo! Curse you, your Posleen and Von Neumann probes all to hell!

    --
    I've been on slashdot so long I'm starting to get out of touch with the cool stuff if it ain't on slashdot.
  35. The title... by xENoLocO · · Score: 2, Funny

    ... kind of reads like a test sentence for a font.

    "Exploding Robots May Scout Hazardous Asteroids" ..

    "The quick brown fox jumps over the lazy dog."

    --
    "The need to build the internet comes from something inside us, something programmed... something we can't resist."
  36. They Sent Malfunctioning Eddie? by good+soldier+svejk · · Score: 1

    The most famous exploding robot I know is rocket car magnate Malfunctioning Eddie. "Hi I'm Malfunctioning Eddie, and I'm malfunctioning so badly, I'm practically giving these cars away."

    --
    It is cowardly, and a betrayal of whatever it means to be a Jew, to act as a white man

    -James Baldwin
  37. UI by mchale · · Score: 1

    I can just picture the NASA folks controlling the robots with an interface based off of Lemmings.

  38. A Drahnasa or two... by Anonymous Coward · · Score: 0

    ...and we'll have self-replicating probe-robots we can sell to a weird race living on a gas giant somewhere in the upper left corner of the galaxy. Hell, let's skip the whole selling thing and reprogram the probes ourselves to uhh, you know... collect information and raw materials?

  39. Japanese? by WED+Fan · · Score: 1

    The exploding robots are part of a Japanese Supervillians group of henchmen, who, as many are aware, always explode spectacularly when hit in just the right way.

    --
    Politics is the art of looking for trouble, finding it everywhere, diagnosing it incorrectly and applying the wrong fix.
  40. PETROL by HTH+NE1 · · Score: 1
    PETRO: People for the Ethical Treatment of Robot Overlords

    Personally, I'd have included the "L" in "Overlords" in that acronym.
    --
    Oh, say does that Star-Spangled Banner entwine / The myrtle of Venus with Bacchus's vine?
  41. Reducing costs even more by mandreiana · · Score: 1
    To reduce complexity and costs, the probes lack solar panels and run on battery power

    Batteries will reduce costs even further, igniting the increasing power of explosions, as seen on laptops :)

  42. What a waste! by Anonymous Coward · · Score: 0

    Instead of going for a dramatic explosion and wasting all the time and money it took to get the robot there,
    why not just have the robot drop off an explosive module and then get it to skedaddle
    somewhere else to help monitor the earth shattering kaboom?

    Look how long the Mars Rovers have been going beyond their planned duration.

    I say let the robots live.

  43. They evolved. They rebelled. by HTH+NE1 · · Score: 1

    I hope they asplode before they turn against us.

    There are many copies. And they have a plan.

    --
    Oh, say does that Star-Spangled Banner entwine / The myrtle of Venus with Bacchus's vine?
  44. Juffo-Wup by lonechicken · · Score: 1

    When these giant masses hurl toward Earth, would the exploding robots help us to more fully understand Juffo-Wup?

  45. Re:Why are we not Performing Collisions? by pln2bz · · Score: 1

    If we could easily push asteroids into a planet why not just push them away when they approach Earth?

    Shouldn't we be trying?

    Do we really need to know the composition of an asteroid before trying to nudge one?

    Seems to me that we just need to know to what extent nudging works, and what sort of complications will arise when we try it. I guess I'm just not sure what the impediment is to trying this right now. I would guess that we'd want to do numerous test runs before expecting that the system works anyways. Is it that we cannot generate enough thrust to displace the orbit or a typical asteroid?

    --
    "A man cannot begin to learn that which he thinks he already knows." --Epictetus, 1st Century A.D.
  46. Sorry... by rubberchickenboy · · Score: 1

    It is now time for the robot on top of your asteroid to explode.

  47. Re:Why are we not Performing Collisions? by HTH+NE1 · · Score: 1

    I don't understand why, when you're trying to understand asteroid collisions with the Earth, you don't perform asteroid collisions with other planets?

    Shoemaker-Levy-9, meet Jupiter.

    Oh right, that was a comet and a gas giant, not an asteroid and an iron core rock-and-water ball.

    Come to think of it, why not set up durable monitoring posts around Jupiter's moons? That should be a more impact-rich scenario. Save money by recording natural impact phenomena.

    --
    Oh, say does that Star-Spangled Banner entwine / The myrtle of Venus with Bacchus's vine?
  48. is your signature a troll? by ClioCJS · · Score: 1

    because if you respond, any down-moderation is undone automatically due to possible conflict of interest.

    --
    -Clio
    Karma: Bad (mostly from not giving a fuck)
    Blog: http://clintjcl.wordpress.com
    1. Re:is your signature a troll? by MyNymWasTaken · · Score: 1

      Ignorant, trolling and/or confusing /. with digg.

    2. Re:is your signature a troll? by FLEB · · Score: 1

      I like it. It's a clever play along the lines of the old "Press Alt-F4 to [do something]" trick (which, I suppose, is a less clever play of the old "Type +++ to [do something]" trick, but that's admittedly before my time).

      --
      Information wants to be free.
      Entertainment wants to be paid.
      You just want to be cheap.
  49. Defective products get another use? Brilliant! by RyoShin · · Score: 1
    To reduce complexity and costs, the probes lack solar panels and run on battery power, limiting their lifetime to a few days. [...] Eventually the probes could detonate onboard explosives, sacrificing themselves for science one by one.
    Seeing the possibility for further profit, Sony has opened an Aeronautical division within the company. The Aeronautical division is planning to take all recalled Sony laptop batteries and sell them NASA, thereby nabbing two birds with one stone. The only potential problem, according to Sony, is the random explosion time of the batteries.
  50. Feel sorry for the last one. by Goldrush · · Score: 1
    Probes that had not yet detonated would listen for any seismic waves sent rippling out from the explosion,

    So the last probe will sacrifice itself for nothing?

    1. Re:Feel sorry for the last one. by DeadboltX · · Score: 1

      The probes run on battery power so they only last a few days.
      If you were the last remaining robot on a lone desolate asteroid would you rather wait out your final hours, dying and withering away while your battery fades.. or would you rather go out with a bang and make it a quick painless death?

  51. Armegeddon by KUHurdler · · Score: 1

    Just wait till Bruce Willis hears about these new robots.

    --
    Fix Your Own TV - RiddledTV.com Avoid the Landfill
  52. Anyone for Antiquing? by Anonymous Coward · · Score: 0

    "I'm alright"

  53. Unlike Star Wars by Dareth · · Score: 1

    Probes do not have to self destruct by design!

    But I guess this will be useful if Aliens discover them. Of course they will be mad as hell at us when they give the probe to their kid to play with and it gets its tentacles blown off!

    --

    I only look human.
    My mother is a halfling and my dad is an ogre, so that makes me an Ogreling
  54. HanSolo by jdigriz · · Score: 1

    "An Imperial Probe droid. Couldn't have hit it that hard, must have self-destructed." -ObHanSolo

  55. I am fluent... by MatrixCubed · · Score: 1

    "I am fluent in six million forms of communication. This signal is not used by the Alliance. It could be an Imperial code."

  56. Re:Why are we not Performing Collisions? by pln2bz · · Score: 1
    Actually, you may be onto something. Maybe the gravitational pull of Jupiter would make it really easy to push objects into one of its rocky moons. Thing is, if the goal is to understand impacts just as much as nudging, Mars is currently the only planet where we could have ring-side seats in place ready to observe the collision.

    As for the cometary impact on Jupiter though, people seem to have conveniently forgotten that the Shoemaker-Levy-9 encounter with Jupiter caused more questions than answers. From http://www.thunderbolts.info/tpod/2006/arch06/0605 29deepimpact.htm:

    Astronomers expected the encounter to be a trivial event. "You won't see anything. The comet crash will probably amount to nothing more than a bunch of pebbles falling into an ocean 500 million miles from Earth." Then came the encounter and an about face. As reported by Sky & Telescope, "When Fragment 'A' hit the giant planet, it threw up a fireball so unexpectedly bright that it seemed to knock the world's astronomical community off its feet."

    [...]

    The Hubble Space Telescope (HST) detected a flare-up of fragment "G" of Shoemaker-Levy long before impact at a distance of 2.3 million miles from Jupiter. For the electrical theorists this flash would occur as the fragment crossed Jupiter's plasma sheath, or magnetosphere boundary. Thornhill comments: "A plasma sheath, or 'double layer', is a region of strong electric field, so the outburst there of an electrified comet nucleus is expected.

    [...]

    Just after the impact of SL-9 fragment "K", HST detected unusual auroral activity that was brighter than Jupiter's normal aurora and outside their normal area. Radiation belts were disrupted. There were unexpectedly bright X-ray emissions at the time of impact. But one mystery was never explained satisfactorily: Early impact events were hidden from the Earth behind Jupiter's limb. However, the Galileo spacecraft was positioned 150 million miles away from Jupiter at an angle that gave it a ringside seat for these events. But Earth-based observatories saw some of the impacts start at the same time Galileo did. "In effect, we are seeing something we didn't think we had any right to see," said Dr. Andrew Ingersoll of Caltech. "...it seems clear that something was happening high enough to be seen beyond the curve of the planet," said Galileo Project scientist Dr. Torrence Johnson of JPL.

    --
    "A man cannot begin to learn that which he thinks he already knows." --Epictetus, 1st Century A.D.
  57. How many times do I have to tell you... by Anonymous Coward · · Score: 0

    Aiming an EXPLODING ROBOT at an asteroid is certain to be interpreted by the residents of said asteroid as an ACT OF WAR. Swift and merciless retaliation will soon follow! We need to stop destructive exploration before we REALLY piss someone off!

  58. Waist of time by G00F · · Score: 1

    This is a waist of time and resources.

    At the most, they find out what that meteaor is made out of, and they plan to use that to speculate what others are made up from.

    Not all are the same. They could be from different planets/moons, or even parts (think core vs crust on earth).

    Rather than figure out what the one they are testing is made of, we should look into ways to change the orbit/destroy meators regaurdless of their composition.

    An early detection system with multiple ways to move it and destroy them.

    --
    The spirit of resistance to government is so valuable on certain occasions that I wish it to be always kept alive
    1. Re:Waist of time by Grave · · Score: 1

      This is a waist of time and resources.

      Apparently, so are spelling lessons.
  59. Except... by interactive_civilian · · Score: 1
    Well, except for the missing F, J, K, Q, and V.

    Take a look a the number of letters of the alphabet that are in "The quick brown fox jumps over the lazy dog."

    --
    "Empathise with stupidity, and you're halfway to thinking like an idiot." - Iain M. Banks
    1. Re:Except... by RobertB-DC · · Score: 1

      Ok, then.

      "Exploding Robots May Scout Fjqvking Hazardous Asteroids"

      Makes at least as much sense as "Jackdaws love my big sphinx of quartz."

      --
      Stressed? Me? Of course not. Stress is what a rubber band feels before it breaks, silly.
  60. Re:Why are we not Performing Collisions? by LiquidCoooled · · Score: 1

    Step one: How (un)stable are these things?

    Without knowing their composition, we could do as you suggest and send a massive probe up there and have it try to land and end up sinking thraight through with no purchase hold.

    Most things you buy from the shops have been tested to destruction, this mission sounds like the toffee hammer approach, we can move onto bigger things when it fails to crack.

    --
    liqbase :: faster than paper
  61. Uh oh... by SlideRuleGuy · · Score: 1

    "Let's try this thing out on _that_ asteroid...it's not headed for earth."
    (BOOOM)
    "OK, now run your calculations on the trajectories of the fragments."
    "Uh oh...."

  62. No Way! by SuperKendall · · Score: 1

    Then research funds could be freed up to build robotic solutions the world REALLY want... sex bots! Woo!

    The last thing I need is an exploding sex bot, thanks.

    --
    "There is more worth loving than we have strength to love." - Brian Jay Stanley
  63. Two great devices that go great together by SuperKendall · · Score: 1

    Hmm, an exploding device that runs on battery power. Where have I head that before?

    Glad they found some constructive use for the Sony battery recall after all.

    --
    "There is more worth loving than we have strength to love." - Brian Jay Stanley
  64. Manufacturer? by Anonymous Coward · · Score: 0

    How about giving Sony a go at making these things? They seem to be pretty good at creating exploding objects lately.

  65. I likey... by DoomHaven · · Score: 1

    ... and I'm responding to mark this awesome thought for later consumption.

    --
    "Don't mind me cutting myself on Occam's Razor"
  66. Re:Why are we not Performing Collisions? by Chris+Burke · · Score: 1

    There are lots of reasons to suspect that our knowledge of impacts is less than we believe. For instance, we *assume* that the reason that nearly all impact craters are round is because the kinetic impact creates an explosion. But there are other potential plasma-based explanations that have been ignored. When two plasmaspheres come into contact, for instance, it is known that electrical interactions can occur. If a significant electrical discharge happens between the ground and the object, then a round crater would form. It may turn out, in fact, that this is the key to disrupting them. We just don't yet know.

    Actually, when two plasma spheres come into contact, there is definitely electrical interactions because plasma == ionized (as in electrically charged) gas.

    Also, we don't assume that kinetic impacts create round craters, the most basic of physics experiment (drop a weight in sand) shows that they do.

    Disrupting any hypothetical electrical charge(it is reasonable to assume that a meteor would become charged travelling through the atmosphere if it isn't already) would involve discharging it, which is exactly what would cause any electricity-related crater. Nevertheless even if you could do this the rather substantial kinetic energy of the meteor would be unaffected and thus a large round crater is guaranteed should the meteor survive to hit the ground.

    Sounds to me like a back-door way to sneak in more of that Electric Universe nonsense, where the most studied, most well understood of the fundamental forces, the one that is most frequently used to do astronomical observations with terrific accuracy, is also simultaneously mysterious and ephemeral, not well understood, and oddly enough denied by main-stream astronomy.

    --

    The enemies of Democracy are
  67. Re:Why are we not Performing Collisions? by der_pinchy · · Score: 1

    Hey dude, I started reading the electric universe and am really fascinated by the whole electric universe theory. I like how they explained the results of the deep impact mission. I dont understand why those scientists keep wanting to insist that theres ICE in those frelling comets when its obvious there isnt. What I havent seen in the book is an explanation for is why some asteriods leave plasma trails and show themselves as a comet and others dont? Or do they all behave like that? They oughta try to simulate the behaviour of these asteriods in a lab by subjecting it to the same conditions in space with plasma and see if they can get them to break like that one that split for no apparent reason. At least try to reproduce it all on a small scale.

  68. overlords reversed by Anonymous Coward · · Score: 0

    Do robotic comet-blasting spacescraft welcome their metric imperial NASA overlords?

  69. Well, it could get worse by zr-rifle · · Score: 1

    They could send them to Uranus.

    (sorry)

    --
    Hack your mind out of its sandbox.
  70. Springs? WTF? by IceFoot · · Score: 1

    The main spacecraft would stay a few dozen kilometers away, perhaps nudging the probes towards the asteroid using springs.

    WTF? How would the mother ship use springs to "nudge" the probe if it's dozens of kilometers away? Does this make any sense at all?

  71. Then it's a.... by DrYak · · Score: 2, Funny
    If that is not a Bush Administration approach to space exploration, I don't know what is :-)

    Simple : It's a...
    BruceWillisBot (TM) !
     
    special "Armagedon (TM)" Edition. (Although no announcement has been made yet, if the CD deck playing Aerosmith will be optionnal)
    --
    "Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
  72. Hmmm.... by LuNa7ic · · Score: 1

    Are they being built by Dells laptop division?

    --
    *runs*
  73. Re:Why are we not Performing Collisions? by pln2bz · · Score: 1

    Sounds to me like a back-door way to sneak in more of that Electric Universe nonsense, where the most studied, most well understood of the fundamental forces, the one that is most frequently used to do astronomical observations with terrific accuracy, is also simultaneously mysterious and ephemeral, not well understood, and oddly enough denied by main-stream astronomy.

    It's always interesting to see people who have not read the details of Electrical Universe Theory talk about it. In fact, I've never witnessed such a willingness amongst intelligent people to misrepresent a subject that they know so little about. I'm determined to be here the day that all of the veteran Slashdotters who frequently regurgitate other peoples' slanders of EU Theory realize that maybe they should have actually read what it said before convincing others that it's wrong.

    It's true to say that we understand electricity and magnetism quite well. It's certainly less accurate to assume that we completely understand how plasma deals with those things. Plasma physics is still an active field. Hannes Alfven liked to comment that although Maxwell's Equations are accepted as rule of law amongst scientists, the plasma apparently doesn't always pay attention to our rules.

    It's a fact that few people actually investigate how it is that astrophysicists came to the conclusion that electricity does not flow through space even though everybody unanimously believes that it's an absurd idea. If you ever decide to investigate it, you might be surprised by what you find. It turns out that magnetohydrodynamics, the field that astrophysicists use to model plasma and other conductive fluids in space, accomplishes its tricks by modeling plasma as a magnetized fluid. They get away with this by asserting that plasma in space is ideally conductive -- meaning it has no resistance whatsoever even over great distances. This assumption applies even to plasmas that extend for light years in space. Consider what they're saying for a second: that inequalities in the charge of a plasma that extends for light years can "readily" neutralize themselves.

    Now, consider another fact. Plasma's physical motions and interactions can induce currents, and the currents through plasma can induce physical motions. 99.99% of all space is matter in the plasma state. In order to conclude that electricity does not flow over this plasma in space, you must conclude that the plasma within the universe, which represents 99.99% of all matter, never violently interacts.

    If you clean your house by sweeping everything under the rug whenever visitors come over, it might seem that your house is quite clean to the people you're showing it to. But over time, all of the crap under the rug will build up. You can hope that people will not pay attention to the lumps in the rug, but they're still there no matter how hard you wish they weren't. Contemporary astronomy is rancid with anomalies that have been swept under the rug in preparation for public consumption (we wouldn't want to confuse them, right?). It never ceases to amaze me how uncritical Slashdotters are when it comes to accepting these processed space stories. It appears that there's little effort to validate any of the *interpretation* or question any of the *assumptions* these days of space press releases in the Slashdot forums. It's especially unusual to me that Slashdot's audience, programmers, are not able to recognize the absence of an input in astronomy. Coders spend all day changing their code to get the right output, and act as if astronomers are able to do the same thing. Astronomy (like archaeology and geology) is output-only, and for that reason, it is highly susceptible to incorrect interpretations, assumptions, prejudices and preferences. There are limits to certainty in astronomy, and the only way to really evaluate problems is to analyze the observational anomalies. If you're skeptical and paying attention, you'll realize that this is not being done. Anomalies these days i

    --
    "A man cannot begin to learn that which he thinks he already knows." --Epictetus, 1st Century A.D.
  74. Codename: L.E.M.M.I.N.G by splutty · · Score: 1

    Low Energy Metal Minion Incinerating New Grounds.

    --
    Coz eternity my friend, is a long *ing time.
  75. Do not taunt... by Luxury+P.+Yacht · · Score: 1

    ... Super Happy Fun Probe

    --
    Bush should have died, not Reagan -- Morrissey
    Morrissey rides a cockhorse -- The Warlock Pinchers
  76. Re:Why are we not Performing Collisions? by pln2bz · · Score: 1

    They oughta try to simulate the behaviour of these asteriods in a lab by subjecting it to the same conditions in space with plasma and see if they can get them to break like that one that split for no apparent reason. At least try to reproduce it all on a small scale.

    We see plasma break apart solid state matter all of the time on a small scale. You can do it at home by turning your arc welder up on a piece of metal until it snaps the metal. Or, when you run too much electricity through a capacitor, a catastrophic leak can occur and damage the structure of the cap.

    By the way, I do a much better impersonation of Big Bangers than you do of EU proponents. I have a *lot* more silly material to work with. Thing is, you'd actually have to read the theory in order to make fun of it, so that makes it much harder for you guys. It must be somewhat frustrating.

    If you ever decide to learn what EU Theory actually says, I recommend Don Scott's new book, The Electric Sky. But if you're the kind of person that values popular opinion over critical analysis and independent thinking, then you might want to skip it. In order to objectively learn the truth about plasma in space these days, it seems you have to be quite impervious to ridicule. Who would have ever thought that playground bullying would be so commonplace in a forum about science and technology? It surprises me every day.

    When it eventually becomes apparent that all of you guys are wrong (if you are lucky enough for this to happen to you instead of your children), people will be entertained by going back through my interactions with all of you. I've always wondered how *I* would feel if I actually realized that I had possibly dissuaded others from reading about a subject because I assumed that it was wrong only to find out that it was in fact *me* that was wrong. I suppose that my level of guilt would depend upon the consequences of being wrong. But you can't know the consequences of being wrong without actually learning what the theory says, so it's an interesting predicament for all of you guys. It's one of the more fascinating dramas unfolding in science today.

    --
    "A man cannot begin to learn that which he thinks he already knows." --Epictetus, 1st Century A.D.
  77. Re:Why are we not Performing Collisions? by der_pinchy · · Score: 1

    Listen you ol crazy thing. Im actaully agreeing with what your saying. I guess youve been mocked so many times its a knee jerk reaction ;)

    What im saying is they need to actaully start crunching the numbers and trying to see if the experiments and numbers jive with what data theyve collected from space probes.

    Yes I allready started reading the book 'electric sky' and im almost through. I said 'electric universe' im my previous post sorry.

    The part that im having trouble believing is where they mentioned the grand canyon and the canyons on mars where made by discharges like some EDM machine. Yea ok theres no delta but even if it cut it down halfway its hard to imagine. They need to look for evidence and see if the power required could happen in the ancient atmos like that.

    I can believe the idea that they say theres no fusion inside the sun. Have they got some technical papers out there that try to run the numbers that would produce the heat and temps with the recorded electron flow from surrounding space? I dont see any refs to tech papers in 'electric sky' for that stuff.

    It mentioed bettlejuice star has a really low density less than our atmos and diameter out to where jupeiter orbits. Of course there cant be fusion in something like that. If the datas right.

    They also showed some stars that changed brightness from bright to dark over a very short period that couldnt be explained by the fusion model.

    Whats the next book to read? i thought about getting 'seeing red' by Arp iirc.

  78. Re:Why are we not Performing Collisions? by pln2bz · · Score: 1

    That's pretty funny. I sincerely apologize. I've never actually met *anybody* on Slashdot who has read an EU book.

    Everybody agrees that quantitative support is lacking, but they're proposing that a complex, interconnected system of transmission lines and loads is occurring. You cannot start to analyze those "circuits" until you understand the transmission line characteristics. That means that we're pretty much starting from scratch. Very little that we've learned about gravity is going to help us to understand the characteristics of electrical plasma. The idealized fluid equations used in magnetohydrodynamics are completely different from the resistive electrical plasma equations.

    I've also seen it mentioned that they have no idea how much of an impact cosmic rays (the solar winds of foreign stars) are having upon the system. Cosmic rays could potentially be distributing energy outside of transmission lines. If you've ever seen an unprocessed space image before, the rawest of space images is filled with extremely bright cosmic rays going in every single direction. There have even been mainstream scientific papers addressing the possibility that cosmic rays are affecting global warming here on Earth. When our own solar wind changes, the number of cosmic rays from foreign stars that reach the planet Earth can change. Apparently, correlation studies have demonstrated that there is a link between cosmic rays hitting the Earth's atmosphere and the generation of certain types of clouds in the Earth's atmosphere. These different cloud types can change the amount of heat reaching the surface of the Earth. This could potentially explain why the temperature of the Earth's surface has been increasing while the temperature of the Earth's lower atmosphere has remained the same over the past few decades.

    Don Scott did a minimalist treatment of rilles (canyons) in the solar system in his book because that topic is covered in great detail online on their www.thunderbolts.info site. That particular issue is best treated when you can present a lot of images and discuss each one in detail. That would have taken up a hundred pages in itself. If you go to their website (Picture of the Day --> Subject Archive), you'll see plenty of evidence that rilles are electrical phenomenon. The most convincing attribute is that many rilles have been observed that follow the terrain both down and up. This single characteristic rules out all of the traditional explanations. You'll also see plenty of evidence that rilles are oftentimes related to round craters. I recommend that if you haven't gone through the www.thunderbolts.info archive of pictures of the day that you might want to consider doing this next. It's basically a whole book to itself.

    I think we'll probably see more details on the Electric Sun idea as time moves forward. Although it was postulated by Ralph Juergens, I don't think anybody's actually attempted to thoroughly investigate it until Wallace Thornhill. I think we're seeing the very beginning of that process. You should also be aware of the Solar Probe mission in 2018. It's a long time from now, but NASA is putting together a mission to try to understand magnetic reconnections and the solar wind by sending a probe as close to the corona as technology can accomplish. I've asked Talbott what he thought the data would say, but he never got back to me.

    Your next choice of book depends upon your interest. There is a lot of material. I've gone through about half of the "Carl Sagan and Immanuel Velikovsky" book. It's dry material and a little bit wordy, but it will fill in a lot of the historical context for how we got to this point. I'm currently slowly moving through Ginenthal's other book, "The Extinction of the Mammoth". The amount of material to absorb is somewhat overwhelming. In addition to all of the books at www.thunderbolts.info, I'm also trying to understand all of the alternative redshift theories out there and historical context for people like Birkeland, Alfve

    --
    "A man cannot begin to learn that which he thinks he already knows." --Epictetus, 1st Century A.D.
  79. Re:Why are we not Performing Collisions? by pln2bz · · Score: 1

    What I havent seen in the book is an explanation for is why some asteriods leave plasma trails and show themselves as a comet and others dont? Or do they all behave like that?

    To answer your previous question ...

    Ever since the Thunderbolts guys recently reorganized their website, the Electric Comet document has become harder to find. You can view it at http://www.thunderbolts.info/pdf/ElectricComet.pdf . This document covers just about all of the questions you might have about electric comets. What you won't get from this document are the opinions of those people who disagree with electrical explanations for comets. You can find lots of those views on the Slashdot forums, NASA press releases and on mainstream websites. By process of elimination, you will notice that the electrical explanations for comets are the only ones that explain *all* of the various observational anomalies that occur with non-electrical attempts to explain comets.

    If you've read "The Electric Sky", then you will notice that Wallace Thornhill predicted the results of the Deep Impact mission. As you learn more about the history of electricity in space debates, you will notice that there is a history of accurate predictions by people who believed that electricity flowed through space, and that in just about each case, the predictions are downplayed by traditional astrophysicists. For instance, Immanuel Velikovsky was able to predict that the surface of Venus would be extremely hot at a time when everybody unanimously believed that the surface of Venus would be fairly similar in temperature to the Earth's. When he then accurately predicted that Jupiter would be emitting radio waves, it was claimed that his accurate predictions were pure luck. Hannes Alfven similarly made a slew of successful predictions related to space plasmas and his success with predictions was overwhelmingly ignored. It appears that contrary to popular belief, a theory's predictive capabilities actually have little to do with its acceptance amongst astrophysicists today because our most popular theories in astrophysics today tend to have after-the-fact, retrospective origins.

    --
    "A man cannot begin to learn that which he thinks he already knows." --Epictetus, 1st Century A.D.
  80. Re:Why are we not Performing Collisions? by Anonymous Coward · · Score: 0

    Hannes Alfven similarly made a slew of successful predictions related to space plasmas and his success with predictions was overwhelmingly ignored.

    What? Maybe you need to read the UU or KTH biography of Hannes Alfven instead of the EUT one. Alfven was a Nobel laureate based on his work in originating magnetohydrodynamics, won the Bowie award for his work with (non-electrical!) comets and astronomical plasmas, and made significant discoveries with respect to the galactic magnetic field and nonthermal synchrotron radiation from astronomical sources. He was very well known in physics communities (he's a Nobel laureate!) and his work, especially in magnetohydrodynamics, remains in use today by many of the astrophysicists you seem to revile.

    (I note also that you claim that Alfven's acceptance speech somehow rejected MHD. No. Read it here: Alfven @ Nobel Institute. His banquet speech was a standard Swedish dinner speech with no technical content wahtsoever; his lecture speech elucidates his idea of the formation of the solar sytem, which is based on his work in MHD for which he won the prize.)

    Alfven was an electrical engineer with some keen insight, mathematical talent, and an insatiable curiosity. He liked to complain that he stepped on toes by being curious about other people's (non-EE) disciplines, but really people in the fields in which he did good work (astronomy, astrophysics, rocketry and hypersonic fluid physics, control theory) were more exasperated by his unwillingness to submit to the anonymous referee system used by most of the large journals in the USA, which reduced the direct first-hand accessability of his theories to subsets of the relevant scientific communities. (He would have liked arxiv.org very much, I guess).

    Yes, Alfven contributed some good stuff to astrophysics, but his Plasma cosmology was not among that. Nobody's perfect!

    It appears that contrary to popular belief, a theory's predictive capabilities actually have little to do with its acceptance amongst astrophysicists today because our most popular theories in astrophysics today tend to have after-the-fact, retrospective origins.

    Theories have to be accurate and useful. Alfven's Plasma cosmologies do not describe the visible universe.

    Most of the scientific proponents of Plasma universe theory have moved on since BOOMERANG, COBE and WMAP's more detailed explorations of the CMB and the Sloane galactic survey have clearly demostrated the existence of a nearly-scale-invariant Gaussian random field, which cannot be explained by any existing Plasma universe theory, and which is a key prediction of Cosmic Inflation. Furthermore, the deviation from perfect scale invariance is exactly the opposite of the prediction made in the final Alfven-Klein cosmology, and the amplitude is several orders of magnitude too low to be compatible.

    Nobody is perfect.

    For instance, Immanuel Velikovsky was able to predict that the surface of Venus would be extremely hot at a time when everybody unanimously believed that the surface of Venus would be fairly similar in temperature to the Earth's. When he then accurately predicted that Jupiter would be emitting radio waves, it was claimed that his accurate predictions were pure luck.

    Velikovsky, however, was no scientist or engineer.

    Venus was already known to be hot by virtue of studies of its blackbody spectrum. Mechanisms were advanced based on the spectral lines which were far more reasonable (greenhouse) than a hot body cooling rapidly to convert Velikovsky's "supercomet" into an ordinary planet. The degree of required cooling of the overall temperature of Venus would have been measurable with then-current astronomical instruments within a year of the publication of "Worlds in Collision". Velikovsky's assertion of an atmosphere rich in long chain hydrocarbon

  81. Re:Why are we not Performing Collisions? by pln2bz · · Score: 1
    I don't have time to respond to all of this just yet, but I did want to excerpt the portion of The Electric Sky that referred to Alfven's 1970 acceptance speech. I wasn't able to find a transcript on the site you directed me to and there is no footnote for the following reference within the book:

    In his 1970 acceptance speech of his Nobel Physics Prize in Physics, Alfven pointed out that this idea of "frozen-in" magnetic fields, which he had earlier endorsed, was false. In reality, moving magnetic fields within a plasma create electric currents. This fact is one of the basic concepts embodied in the Electric Sky.

    Hannes Alfven was unique among Nobel laureates in taking the opportunity of his acceptance speech to declare that he had been wrong in what he had said previously. Alfven said, "I thought that the frozen-in concept was very good from a pedagogical point of view, and indeed it became very popular. In reality, however, it was not a good pedagogical concept but a dangerous 'pseudo-pedagogical concept.' By 'pseudo-pedagogical' I mean a concept which makes you believe that you understood a phenomenon whereas in reality you have drastically misunderstood it."

    When he used the term "classical plasma theory", Alfven was referring pejoratively to this erroneous "frozen-in" idea and its cause -- the false assumption that plasmas are "ideal conductors." When discussing the failure of this so-called classical approach in the search for controlled nuclear fusion, Alfven pointed out that:

    The 'thermonuclear crisis' did not affect cosmic plasma physics very much. The development of the theories continued because they largely dealt with phenomena in regions of space where no real check was possible. The fact that the basis of several of the theories had been proven to be false in the laboratory had very little effect. One [astrophysicist] said that this did not necessarily prove that they must also be false in the cosmos. Much work was done in developing these theories, leading to a gigantic structure of speculative theories which had no empirical support
    A response on the BAUT Forum at http://www.bautforum.com/showthread.php?t=42173 apparently responds:

    Yes, you have misunderstood. What Tim said, and what your quotes say is that frozen in is an approximation based on the resistivity and lifetime of the plasma. In the strictest sense, fields are not frozen in since there is always a resistance. However, if the field movement is small during the lifetime of the plasma, you can do an approximation and say it is frozen.
    On that same topic, Tim Thompson responds:

    MHD and "frozen in" are by no means synonymous, and you should not confuse them. Yes, that was the crux of Alfven's later work. That's what I was talking about when I said, "I think you will find that a rift deveolped between Alfven & the astrophysical community". Having developed MHD, Alfven then tried to abaondon it. He was wrong. MHD is applicable almost everywhere, and almost everyone except Alfven saw it. Modern plasma astrophysicists use MHD appropriately, and realize that the closed current models of Alfven are not in fact generally applicable, and are in fact generally wrong (but there are exceptions to every rule, which is why I also said, "One has to study these things on a case by case basis").
    I don't see any problem with my assertion except that I should be more specific in referring to the frozen-in concept *within* MHD.

    I have to check out for a few days, but I'll take a closer look at your response later.
    --
    "A man cannot begin to learn that which he thinks he already knows." --Epictetus, 1st Century A.D.