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Science

Europe plans comet landing 116

El Jefe writes "The European space agency has plans to land on (a shoot a harpoon into) a comet. The spacecraft is called Rosetta, and is supposed to rendezvous with the comet Wirtanen in 2012. " And all this time I thought cheesy Hollywood blockbusters where astronauts landed on asteroids had no scientific basis. I find it interesting, however, that the spacecraft will secure itself to the comet through the use of a harpoon.
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Europe plans comet landing

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  • by Anonymous Coward
    I read somewhere that the best way to get on a comet is to hire some oil drillers and put ski's on the Shuttle instead of wheels.
  • by Anonymous Coward
    Doesn't this brilliant idea have the possibility of altering the course of the comet? The lander may extremely light, but isn't it possible that it can slightly alter its course because of it? What aftermath effects could this have?
  • by Anonymous Coward
    Flower Power!
  • by Anonymous Coward
    Okay, what happens if the comet is mostly made of dust -- not ice?

    "Whoops!" says Ground Control, and the harpoon pulls out a plug of dust bunny and the Rosetta tumbles out into the void.
  • by Anonymous Coward
    That's not enough, because the energy released by a megaton-class bomb is near zero compared to the comet's kinetic energy:

    The comet is 3 miles (4800 meters) in diameter, so its radius is about 2400 meters. Assuming its density is equal to that of water (which definately is a best-case scenario), or about 1000 kg/cubic meter, its mass is:

    m = 4/3 * pi * radius^3 * density = 5.8*10^13 kg

    (about 60 billion metric tonnes).
    In order to calculate its kinetic energy we need its velocity. As we are interested in an order-of-magnitude calculation here, we'll just put in something in the same order as the earth's orbital velocity: about 30 km/s (3*10^4 m/s).
    That means the comet's kinetic energy is:

    T = 1/2 * mass * velocity^2 = 2.6*10^22 J (Joule)

    And now for the nukes: a tonne of TNT is equivalent to 4.18*10^9 J of energy. So a megaton-class device will only yield something in the order of 4*10^15 J.

    Bottom line: the bomb will yield an ammount of energy that is only 1.5*10^-7 times the kinetic energy of the comet (that is: only about 1 ten-millionth part of the comet's kinetic energy), so changing its trajectory will require something more than just a nuke.
  • Actually, we *could* use parachutes, but they'd need to be really really big -- kinda a reverse solar sail.

    ----

  • Posted by Lord Kano-The Gangster Of Love:

    We're not talking about something that only weighs a couple of tons.

    Even though I don't know the specifics of this comet, comets can be several miles in diameter. For the sake of arguement let's use 3 miles as the diameter. Three miles thick made up of water, rock, and metal, three VERY heavy materials. Moving VERY quickly as well.

    Imagine what a piece of steel the size of a minivan could do if it were moving at the same velocity as a bullet. Now imagine a 3 mile wide piece of water and ferric rock moving as fast as a bullet, now twice as fast, and so on. We don't have the technology to even alter it's path. We're a LONG way away from being able to stop it. We can't throw parachutes on it and wait for it to stop.

    LK
  • Posted by Lord Kano-The Gangster Of Love:

    Making the assumption that this takes place in the future and we can actually build a solar sail that large, and we have materials strong enough to stand that much force, and we can anchor them strongly enough to the comet, we're fucked if it's coming at us from the direction of the sun. No?

    LK
  • Posted by Lord Kano-The Gangster Of Love:

    I have heard of it, but I don't exactly how it's done.

    LK
  • Posted by Lord Kano-The Gangster Of Love:

    Since we've never been able to study a comet's composition it's still speculation what material makes up most of the mass.

    When you breakdown water into hydrogen and oxygen and burn them the exhaust is water. Why waste the energy? Just melt it and try to find a way to get rid of the water before it re-freezes.

    As to what they're made of, 20 years ago comets were thought of as "dirty snowballs", 10 years ago some astronomers began to think of them as "snowy dirtballs" who knows what they will think 5 years from now. I suppose that the best thing about this "comet landing" is that we will know FOR SURE what the composition is. Well, at least of this one comet.

    LK
  • This was actually proposed by Dr. Robert Forward as a means of propulsion. He wrote sci-fi novels (see Saturn Rukh) but had a hard scientific basis for it. Look it up at his site [whidbey.com] and look up HoyTethers.

  • If the harpooning is not done automatically but is controlled by folks on the ground, will the controllers saying "Thar she blows!" and calling their chief Captain Ahab?

    Call me Ishmael.
  • Yeah, it'll probably alter the orbit slightly, but the active jets that form on the surface of a comet during a pass through the inner solar system will probably change the orbit even more.

    The orbital mechanics folks have seen orbital anomalies in comets that have been partially attributed to outgassing in particularly active regions on a comet, the rest can usually be blamed on Jupiter.

  • Your logic is flawed. And unfortunately, that is what most people listen to, stuff like "it only happens every 100,000 years."

    That's total BS. Sorry, but it is!

    They are not regular events that can be predicted. They are not something that we know were safe from because it hasn't been 100,000 years yet!

    When you get in your car to drive to work, do you say, "The average person only has 3 serious accidents in thier driving carrer, and since that's at LEAST 30 years, that is more than 10 years between accidents. Since I had an accident 3 years ago, I am safe for another 7 years! I can drive how ever I want, and will not get into one."

    The fact is, actuary tables (spelling?) show that the most threatening thing to mankinds existance today is a comet/meteor/astorid impact. The probability of it happening, and the damage it could cause are well calculated. And, it is a HUGE risk that people just ignore because they follow your way of thinking about it, which is flawed logic.

  • by BadlandZ ( 1725 ) on Friday July 02, 1999 @06:15AM (#1820968) Journal
    Well, when it comes to calculating the potential risks, a comet/asteroid impact on the earth is one of the biggest threats to man kind we face.

    One problem is, the US government spending is influenced by the people, and the people all went to see "Star Wars" and think NASA should focus on space travel. It's somewhat short sighted. Trying to figure out a way to populate other planets with people from earth is a very very long and very very expensive process. A true danger that NASA could be working on is to develop a defence against asteroids.

    Look at all the craters in the moon. It's evidence that nasty stuff happens. We don't see those craters here on earth, not because they never have hit, but because the rain, weather, wind, etc.. have washed them away. The earth is a bigger target.

    Some scientists, even those -outside- the study of space, have started to deticate some of thier time to inform people of these dangers... Kary Mullis comes to mind (he is a Nobel winning chemist, so he is invited to speak at a lot of events. He is asked what he thinks of "global warming" and he acknoledges it, but makes it clear that he does not view it as our biggest threat, because we see it comming, and people can generally adapt pretty well. But, he has started to make a point to talk about dangers of asteroids in every talk he gives, just to spread awareness. And he isn't even an athority on it, just an example, the first person that came into my mind).

    Star Trek and Star Wars are good entertainment, but so is Beavis and Buthead, and South Park. Just because thier cool to watch doesn't mean we should try to do what the people in the shows do. Hollywood isn't known for it's accuracy or scientific achievement.

  • send up a ship with some powerful engines to drop a bunch of harpoons into the thing & tow it back to Earth? They could haul it to the space station & cut it up before bringing it down in pieces on the shuttle. ;-P

    Probably freak out aliens in a distant system though. "Hey, that comet was supposed to be back this year...."

    -Rev. Randy

  • This reminds me of the book by Brin and Benford, "Heart of the Comet". Very good book, I liked it more than any of Brin's others.

    Benford? I've tried to read one of his (Timescape). Eww. I like hard sci-fi, but I hate the total lack of character and character development.

    -Billy
  • The mass (and momentum) of a spacecraft is much less than that of a comet, so the effect will be minimal. However, even without our prodding, some comets do hit the sun - see
    http://umbra.nascom.nasa.gov/comets/SOHO_sungraz ers.html



  • i'm glad all these centuries of whaling technology hasn't gone to waste.

    -l
  • DS4 was one of my favorite mission.
    :-(
  • Aside from the near-difficulty (read "impossible" without Star Trek engines or a couple centuries of lead-time) of being able to shift a comet's orbit enough to force an intercept with the Earth, would you want to be responsible for providing the precise delta-vee to place it in an orbit about the Earth? And how about orbit-keeping adjustments to keep the orbit from decaying?
    Christopher A. Bohn
  • to keep it from bouncing off. The comet just doesn't have enough gravity for a traditional soft landing.
    Christopher A. Bohn
  • You're right. I mixed aphelion & perihelion.
    Christopher A. Bohn
  • A comet's orbit is defined by the same laws as any other. Some comets (primarily "long period" comets) do travel remarkably fast as the progress through the inner solar system (but at the same time progress quite slowly through the outer solar system). Others don't (Comet Eike comes to mind). And, no the "yank" won't affect the comet measurably at all -- consider the mass of the comet and the mass of Rosetta, and you'll realize it'd be analogous to a fly pushing off against your arm.
    Christopher A. Bohn
  • The problem is "nongravitational accelerations" -- a comet's orbit, unlike most other bodies in the solar system, changes from orbit to orbit. The outgassing provides accelerations that subtly change its orbit. While accelerations so close to aphelion have less effect than if they were near perihelion, they still make it difficult to precisely predict its next orbit. This should only raise a concern if it was already going to be passing close to the Earth in one of its future orbits -- the change is too subtle to cause drastic shifts.
    Christopher A. Bohn
  • When Halley's last visited, they launched a probe called Galileo. Did that land on the comet or just come really close to it?
  • Yes, it was Giotto. Don't know what I was thinking. Still, that was a while back and I was much younger and care-free.
  • Who is being arrogant now?
  • But the US is attempting it in 2005.


    The problem is that the NASA just cancelled Champollion. 8(

    It seems that the combination of Clinton's budget cuts and the money-sucking pit known as ISS are having some severe impacts on NASA. On top of that, Dan Goldin keeps sucking up and saying how happy he is to "do more with less". The problem is that the real science at NASA has started to suffer to an ever-increasing degree.

    Of course, Goldin hasn't cut Al Gore's pet satellite, Triana.So, in exchange for bailing on new, potentially exciting planetary science, we are going to get a screensaver of the Earth and a few rich Russian cosmonauts.
  • I apologize for dragging a previous thread into this one, but I could not resist the temptation to suggest putting Jar-Jar Binks and the machines responsible for his development on the comet.

    I'm dissapointed that the United States recently shelved their plans to do a very similar thing, citing that there are better things to spend our money on.

    When the comet comes (and we all know that, eventually, it will) we're all going to regret that we had paid a little less to build sports stadiums and provide corporate welfare and a little more on space research.

    And if anyone questions the odds of a comet hitting? They're better than the odds of winning the lottery. And almost every lottery has a winner...
    ---
    seumas.com

  • I mean Rosetta has only been worked on for the last decade....

    People started work on Rosetta before Linus started work on Linux.

    Anyway - this is an amazingly cool mission, but I'm not sure of their chances of orbiting a small outgassing body, especially since the measurements of the comet make it look smaller and smaller every time we look at it ;-)

    Stardust is the US response - they want to fly through the tail of a comet and pick up dust in an aerogel capture system for return to earth.

    Rosetta looks much more interesting.
  • Actually, the main reason that our craters are far less numerous is that we have an atmosphere. The vast majority of bits and pieces burn up into things little larger than pebbles.

    That said, there still is that nice crater in the Yucatan... The one they think killed the dinosaurs.
  • Dhink unexbected zide evvects. *ACHOO* *ACHEE* *snort*. Goddamn little critters are bervectly gapable of knocking me over! *snort*
  • by Splat ( 9175 )
    It has to work!@# I mean, they did it in Armageddon, right?!
  • an anchor than a harpoon. This is a harpoon like screw anchors are harpoons. Usually you harpoon something from far away, unless you are playing Ahab riding the whale.
  • NASA cancelled the comet-landing probe [yahoo.com] earlier this week:

    Hmm... the URL doesn't work, even though I cut and pasted it exactly. Damn Yahoo. Anyhow, it's http://dailynews.yahoo.com/headlines/ap/science/st ory.html?s=v/ap/19990628/sc/comet_lander _1.html

  • Of course, Goldin hasn't cut Al Gore's pet satellite, Triana.So, in exchange for bailing on new, potentially exciting planetary science, we are going to get a screensaver of the Earth and a few rich Russian cosmonauts.

    Amen. I couldn't have said it better myself. I'm involved with several experiments scheduled for ISS, so I personally see the effects of CHEAPER part of Goldin's mantra.

    Fortunately, NSF is finding some real science to add to Triana (GoreSat). I still personally don't see the justification.

    ~afniv
    "Man könnte froh sein, wenn die Luft so rein wäre wie das Bier"
  • Well, the Ahab method of hitching a ride's probably better than the 'Bug on the windshield' as far as the probe surviving is concerned...
  • Well, I don't think it was a "guess", exactly. The orbit of Halley's comet is pretty darned well-known. (Though it is pretty darned cool that we're beating him to the punch by over fifty years by landing on a different comet.)
  • The 2003 NASA mission the article talks about was scrapped June 29th. The link to the story can be found at the bottom of the page from the article above.

    Or just go
    here [cnn.com]
  • I agree, Ishmael.

    Rosetta is horrible name. At the very least, the name should be changed to Queequeg.
  • Better idea: stick a big flashing light and radio transmitter on it, so we know when it's coming round again. Hey, maybe we could get a Linux box put on a comet!

    "I want to use software that doesn't suck." - ESR
    "All software that isn't free sucks." - RMS

  • Umm,

    Tagging comets doesn't get rid of the problem of getting squished by an untagged one. I'm sure that the cost of 'catch and release' on the astronomical scale would be better applied to a concerted and systematic observation and early detection system, or even a tactical nuke base on the moon. :) If the threat of nuclear retribution was enough of a deterent to make the US and USSR play nice, I'm sure it would work on an iceberg. :)
  • The trouble with asteroids is that while the risk may be great (we are reasonably certain it's led to mass extinctions before), the risk in any given time period -- say, a human life of 75 years -- is rather small. This leads to an underappreciation of the overall risk.

    Nobody needs to lose sleep over this; the largest impact we've seen this century is Tunguska, and the odds are still rather small that a Tunguska event will strike a populated area. On the other hand, the odds are higher that an impact tsunami will cause widespread coastal destruction and loss of life. Our only chance is to have sufficient warning time. By definition, an undiscovered object could strike with warning time == zero. It's estimated that we know of maybe 10% of the large-enough-to-hurt-sized rocks that cross the earth's orbit, so the job of finding them isn't trivial.

    The good news is that there is modest funding for a hazardous objects search.

    The NASA Impact Hazards site [nasa.gov] has lots more info, including the search project called "Spaceguard".

    My take on this is not so much worry that something might happen, as sardonic awareness that it would be Really, Really Stupid to finally figure out this is a problem (last 20 years) and then have our civilization wiped out. Especially if we really are the only intelligent one around ...
  • Because it's true, that's why. The US funds science missions at a small fraction of the money spent on the largely useless manned space program. (Q. Why do we send people into space? A. So we can learn how to send people into space.)

    The Europeans are justifiably proud of their space science program, which is a much higher portion of ESA spending, and in particular (like the Japanese) seems to be a little more skilled overall at meeting deadline-oriented projects.
  • Three words: Conservation of Momentum.

    Even if it's small, it's going very fast -- generally 10 or more times the maximum speed that any human-built spacecraft have ever achieved (including via gravity assist).

    Now assume we have a spacecraft with ten times the capability of anything built today. You would need to have it rendezvous with the comet at the edge of the solar system, then expend all its fuel slowing down an object that's at least a factor of 100 larger in mass than itself, and .... well, if you could do that, you might be able to achieve placing its orbit into a slightly lazier circle that wouldn't get as much acceleration from the sun. Repeat this ten times (in ten 20-year cometary orbits) and you might get a comet that you can aim roughly at the earth.

    Which you would want to do, why?
  • Are you suggesting there should be one news article when a project is started, and no more news articles on that project until ... when?

    Sheesh.

    Slashdotters are very spoiled. Instant news! Worldwide distribution! Five minute lead times!

    "Hey, I've known that since at least yesterday!"

    "This was posted in a response to slashdot item on Linux clustering that drifted into a discussion of planetary orbits. Since I read everything on /., I've known about it for three hours and fourteen minutes already, why is Hemos wasting my time with old news like this?!"
  • And, presumably, wouldn't be able to pronounce it's own name.
  • Sorry - I was making a dumb joke. The not being able to pronounce own name thing was a reference to Star Trek I, where "Veeger" turns out to be Voyager. And stuff.

    Ahh. Dumb reference. Nevermind. :)
  • Actually if memory serves me right it was called Giotto. Got some pretty good pictures of Halley's nucles too before it got whacked by a high speed dust-bunny.
  • One problem is, the US government spending is influenced by the people, and the people all went to see "Star Wars" and think NASA should focus on space travel. It's somewhat short sighted.
    Trying to figure out a way to populate other planets with people from earth is a very very long and very very expensive process. A true danger that NASA could be working on is to develop a defence against asteroids.

    I'm not arguing against an asteroid detection system -- it's vital to Earth's long-term survival -- but a permanent presence can be established on Mars for half the cost of the ISS. Check out the Case for Mars [colorado.edu] site, or read Roger Zubrin's book of the same name (hope I got his name right).
  • We could use actively generated radio signals rather than reflected visible light to locate the comet when it comes 'round again. this would make them a lot easier to locate, as the surface of a comet has a pretty low albedo (think dirty snowball, where all the snow has melted).

    As another poster noted, the orbit can change. Tag enough comets this way and we'd have YEARS of notice of potential comet collisions, rather than a few months. (hmm...that's make an interesting RPG scenario...the Comet Beacon Team...) But what power source could you use that would last for hundreds (or thousands) of years? How do you make sure the transmitter doesn't get blown off by a bit of steam without burying it so deep that no signal can escape?
  • Giotto is still up there and is due to fly-by the earth this month

    Although damaged by it's close encounter with Halley's comet, the probe was reused to study Comet Grigg-Skjellerup on July 10, 1992.

    For more info, have a look here. [nasa.gov]

  • Let's hope we can get some real samples (or at least spectroscoped/gas chrom'd images) back to Earth. If complex carbon compounds are found onboard the comet, it could confirm several theories about how life developed.
  • NASA hopes to do something similar in 2005 -- check out the ST4/Chompollion mission site [nasa.gov]. (The ST4 project used to be called DS4, one of the New Millenium missions)
  • Ok, ok, so I jumped the gun. NASA sucks for cancelling ST4. (But they don't suck in other areas, so I'm not heartbroken :)

    -g.
  • The CNN report is inaccurate, the NASA cometry
    mission called ST-4 or Champollion has been
    cancelled because of budget pressure. It seem
    they had to choose between that and the Mars 2001
    lander. They kept the Mars misson as more of
    the money has already been spent.
    Details in http://www.spaceviews.com/


    PS How come this is news now? There have been
    details of the mission on the ESA web site for
    at least 2 years. Work started on it
    in the early 90's.
  • If you look at the bottom of the article, you'll see a link to another article titled NASA scraps comet mission [cnn.com]. That's why the ESA said that they'd win the comet race.
  • When something is as massive as a comet, you need some really big horkin engines (technical term) to move said comet. We (humanity) don't have those engines. Even a little orbital adjustment of a small comet would be extremely challenging. If this comet is large enough to navigate a spacecraft to it and lang on it, we can assume it's too large to move.
  • by MACC ( 21597 ) on Friday July 02, 1999 @04:21AM (#1821016)
    have a look at :
    http://www.mpae.gwdg.de/mpae_projects/mpae_project s.html

  • With the goal of Linux being World Domination, some friendly aliens would probably help it out and rename it to VGER and try to kill us all.
  • Comment removed based on user account deletion
  • Hasn't this already been discovered? I seem to recall something about spectrographic analysis showing this (and/or amino acids) on some comets.
  • So when is Greenpeace going to launch it's protest spacecraft?
  • The second "sequel" to 2001: A Space Odyssy features landing on the Halley comet. Guessed right, the next visit is on 2061. Actually, it's one of the best in the series, so go get it if you still haven't read.

    You know, according to the "hacker" hype, we have to deal with sci-fi extensively. No problem with me though, I just love sci-fi.
  • A joint mission between NASA and a Japanese counterpart is planing a mission called MUSES-C [isas.ac.jp]. It is supposed to drop a tiny rover on an asteroid.

    It does not seem to use a harpoon, though :-)
  • No no, hamster power is the way to go
  • "The United States launched its first comet mission in February -- the Stardust spacecraft, which is to pass within 140 km (90 miles) of the Comet Wild-2 in January 2004. The mission hopes to be the first to capture dust from a comet and return it to Earth in 2006. "

    Ok this is off topic, but, can anyone confirm or deny that the Stardust Casino and Hotel is actually named after abomb fallout, because it was constructed during the period of time when atomic testing occured in Nevada? I have a long standing bet with a friend, and we can't nail this down. I read this a long time ago, but can't find it now. If you look at the stardust sign with all the lights, it looks like an abomb..
  • Gravitational affects of being in the inner solar system have much greater effect on changing the orbit. Since outgassing is affected nearly logarithmically by distance from the sun, they are much more concentrated at apihelion. If we can watch it leave the inner solar system we should have enough info to predict return within a day or less.
  • As for the delta-vee, why not just plop it down at L4 and it will stay put (as long as the moon is orbiting the Earth.) It's not the shifting of orbit, it's the deaccleration to get it to stay.
  • This was most likely some french guy with an inflated ego due to his country's revival of the "Le Meridian" and Paris mean time. le meridian [bbc.co.uk]
  • And you know how we Europeans come up with such great ideas as this 24cylinder coupes and other such useless gimmicks? Our Engineers have their daily ration of CRACK...
    It speeds up the development of stupid ideas by a factor of 10
  • already have samples ....
    a probe that fluing itslef through the tail of some comet recently had a little bit of aerogel in it ( 2% the density of air ) . It captured particles that contained carbon compounds .
  • Check this article in Scientific American [sciam.com]. Great overview.
  • I think the people who live close to the ozone hole might think that human impact on the environment is a more serious issue. That said I agree that we need to invest far more capitol in all phases of the space program, including comet/realy big space rock detection.


    Of course, the point can be made that our best defense, as a species, is to get off this rock. To that end support Mars Direct and the Arctic Research Station [marssociety.org].

  • I'm not sure what info we could get from having a beacon on a comet. After all, we would be able to pretty accurately compute its orbit after a month-long rendevous. But it would be so cool! ;)
  • So you expect GREENpeace to rush out and protect a dirty snowball....

    uh huh...
  • It will alter its course... its a simple question of kinematics...

    Fortunately, however, the force of the lander touching down must be very slight in order to protect all of its valuable equipment. Take that reciprocal force on the comet and divide by the comet's mass (vastly greater than the landers, at least in the 100's of thousands, if not millions of times greater) and you have an insignificant force.. particularly compared to the streams of ionized gas coming off the surface

    A decent analogy would be when a dust mite lands on your arm... doesn't exactly knock you over.

    Doug
  • If we did get a linux box on it and a sufficient energy supply, could you imagine the uptime when we saw it the next time?
  • nah, we should just let it soar by and hit the alien colonization. Unless they are intelligent enough to try and land two space shuttles on it and dig 800 feet deep and drop a nuke down in it and detonate it remotely before it hits zero barrier (hmm, sounds kinda like a movie to me... Arma-who?).

    ;)

  • is about the only practical way to do anything significant to the orbit of a comet.

    If the comet has a lot of high-vapor-pressure stuff (methane, water, frozen hydrogen, very small rocks...) a big black tarp set up just right might have interesting effects...

    Fear my wrath, please, fear my wrath?
    Homer
  • The part of the mission I am familiar with is CIVA. This is an instrument on the lander (ROLAND I think) that has an infrared imager and a visible imager (the orbiter also has imagers). The imagers will be used to do spectroscopy on core samples of the comet: the lander will drill a sample from the comet, then illuminate it with light of different wavelength, and image it. This should give spatial information and chemical composition.

    Of course, this assumes the spacecraft launches safely, rendezvous with the comet safely, lands safely, the instruments work, the radios work...

  • And yes, on the outward bound leg it could be coming at us from the general direction of the sun.
  • by Aarfy ( 58811 )
    Heh heh I think you meant this response to the previousstory.

  • Or better, stick ole Bill on it ;)

    Mong


    * Paul Madley ...Student, Artist, Techie - Geek *
  • Maybe when we next saw it, the box would have developed AI and would come back... angry.

    Mong.

    * Paul Madley ...Student, Artist, Techie - Geek *
  • And without anyone to teach it to speak... urgh.

    That said, when it comes back, it'll probably be running Windows3000 and have a disclaimer denying the existence of any product from any company not a subsidiary or affiliate of the Microsoft World Government.

    Mong.

    * Paul Madley ...Student, Artist, Techie - Geek *
  • Yep, the best way to determine if life was brought to Earth from comet impacts is to spear one, drag it so that it impacts Earth, and study the results. dOh!

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