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Space Science

More Evidence For An Extinction Comet 171

Andy_Howell writes: "There is more evidence that a comet or an asteroid is believed to be the cause of another mass extinction. This one happened 250 million years ago, long before the one that killed the dinosaurs, it and wiped out most of the life on earth, including the trilobites. The evidence comes from buckyballs with unusual isotopes trapped inside -- isotopes that were apparently created in carbon stars."
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More Evidence For An Extincation Comet

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  • by Anonymous Coward
    Doesn't surprise me either.. I knew that this whole Open Source Linux thing was a Communist conspiricy all along. Why do you think they call it "red" hat? It's all so obvious and I'm glad that someone like Allchin finally got the balls to stand up against it. Maybe this whole spy thing will get the attention of the lawmakers. Did you know that Finland (Where the communist who started it all and is now spying on high tech companies in Silicon Vally) is right next to Russia? Coincidence? I think not!
  • The following is due to Andrew Glikson (at the Australian National University):
    The suggested genetic connection between a ... Permian-Triassic boundary impact and the Hawaiian hot spot track, based on iridium anomalies (H. Burchard) ... needs to be placed in perspective in view of (1) the significance of Ir anomalies, (2) the onset of the Hawaiian volcanic chain, and (3) the origin of the P-T boundary extinction.

    Anomalous concentrations of iridium can result from several factors: (1) contamination of crustal rocks by asteroid impacts; (2) Ir-bearing basalts and volcanic volatiles, such as measured at Kilauea, Hawaii; and (3) Ir and other platinum group elements (PGE) absorbed by marine algae and organic matter present in black shale.

    However, PGE abundances in chondrites are more than two orders of magnitude higher than in the Ir-enriched volcanics. Compare the mean PGE levels in C1-chondrites (Pd ~ 490 ppb; Re - 35 ppb; Os ~ 510 ppb; Ir ~ 450 ppb) with those in typical basalts (Pd ~ 0.6 ppb; Re ~ 1.0 ppb; Os ~ 0.1 ppb; Ir ~ 0.05 ppb) (cf. Chou, 1978, 9th Lunar Sci. Planet. Conf., 219-230; McDonough and Sun, 1995, Chemical Geology, 120, 223-253). PGE abundances in impact fallout deposits, although diluted, are still commonly higher by an order of magnitude compared to volcanic rocks, for example Moreover, the ratios between the volatile PGE (Pd, Re) and refractory PGE (Os, Ir) effectively discriminate between meteoritic and terrestrial materials thanks to the preferential enrichment of volatile PGE in crustal rocks relative to the mantle during magmatic fractionation. For example, typical crustal Pd/Ir ratios (~12) and Re/Os ratios (~10) are higher by over an order of magnitude compared to typical meteoritic Pd/Ir ratios (~1.0) and Re/Os ratios (~0.07). Isotopic discriminants between terrestrial and meteoritic materials include high 187Os/188Os ratios and intermediate 52Cr/53Cr ratios.

    Both primitive Hawaiian basalts and volcanic volatiles show typical terrestrial-type PGE abundances and ratios, for example high Pd/Ir ratios and Re/Os ratios (Bennet et al., 2000, Earth Planet. Sci. Lett. 183, 513-526), and are therefore highly unlikely to represent signatures of meteoritic components. Significantly, the oldest volcanics dated at the northwest extremity of the Emperor-Hawaii chain are about 65 Ma ... Therefore, neither the PGE geochemistry nor structural evidence of which I am aware connect the Emperor-Hawaiian chain with the Siberian Norilsk plateau basalts of Permian-Triassic boundary age (248-251 Ma).

  • by Anonymous Coward
    The question would be, in this case, whether or not this can be considered part of the normal evolutionary process.

    The article quotes one of the researchers saying that life has to adapt or die. In this case, does that indicate to us that the world is better for it in the end? The life that has adapted - perhaps it is stronger. Less affected by change in its environment.

    Perhaps it's the very reason why human beings are able to colonize the majority of this planet. An amazing ability to adapt, brought in through the evolution caused by the nature of the universe itself.
  • by Anonymous Coward
    I know you're probably just trolling but some idiot might read this shit and take it seriously. Lets go at this one at a time. First of all the moon. Yes, the moon is receding from the Earth but it is NOT receding at a "constant rate" as you say. Furthermore no current theory places the formation of the earth of the moon at the same time! So the limit you mention (the "Roche limit") does not even come into play. But then when was the last time that a creationist could do math.

    Your comet example is even more ridiculous. You assume that the solar system was poofed into existence with comets in their current orbit. The truth about comets is that they burn up all the time and are constantly resupplied from sources like the Kuiper Belt and the Oort Cloud. Look at all the comets that we know of, their ages all VARY, just like you said! If they were all created at once don't you think they would all be the same age? Short period comets have short lifespans, astronomically speaking! The fact that we see lots of comets with lots of different ages is proof that they are resupplied and perturbed into solar orbits with time.

    In short you are either a troll or you have been duped by televangelists. Try thinking for yourself once in a while. You'll be a lot happier.
  • by Anonymous Coward
    The important thing to realize is that the article talks a meteorite as a mere initiator of a whole series of events which would ultimately be responsible for a mass extinction. You wouldn't believe the possible chain of events which would occur after the right trigger. Assuming that science has a very good and clear view of the eventual outcome is nonsense. This also implies that a (possibly human-inititated) global warming might lead to (a very) unpredictable outcome. Once there is enough fresh water around the poles the global re-distribution of warmth/energy by means of the major ocean currents stop (there is evidence for this). And europe/northern america might just get very very cold indeed. As for the PT boundary, i have those chinese samples here on my desk, getting "noble gasses out of a buckyball" is a major achievement, not easily done in most labs. Congrats. Wouldn't even think of starting experiments like that myself.
  • by Anonymous Coward
    This one happened 250 million years ago, long before the one that killed the dinosaurs, it and wiped out most of the life on earth, including the trilobites.

    They killed the trilobites! You bastards!

  • by Anonymous Coward
    >>...the moon. The moon is receding from the Earth by a small amount every year.

    Yup. Consistent amounts? Predictable amounts? Guaranteed to continue to receed?

    >>There is a minimum distance that the moon must be from the Earth in order to remain in orbit.

    Yup. Otherwise it'll zoom off into space, or crash into us. Thankfully, we need not prep any miners anytime soon.

    >>If the Earth is billions of years old as evolutionists say, there is no way that the moon could exist as it does today.

    Wrong. Mayhaps the moon isn't as old as the earth. Or perhaps the orbit of the moon varies over time, and it will come closer again in the future. There are many sources of gravity that can come into effect. Orbits are never are simple as we like to imagine.

    >>Another example is comets. Comets have a limited lifespan. Every time they pass by the sun, they burn up some of their mass.

    Yup. Ice, typically.

    >>If the universe was billions of years old, comets would have long since exhausted themselves of their own mass.

    Unless they pick up more mass on their travels. Perhaps small comets combine into larger comets in the (?postulated?) Oort cloud.

    >>Yet we still see comets and can tell by their rates of decay that they are young (their ages are in the range of 1,000 to 6,000 years.)

    Really? Evidence for this would be nice. Rate of ice-burnoff relates to age? Sounds implausible on the face of it.

    >>None of this even comes close to a 13 billion year old universe.

    Assuming your 'evidence' is acceptable, true. But comets != entire universe. Even if all the comets we've seen are young, that says nothing about the age of the universe as a whole.

    Evidence to the contrary:
    1. Extremely distant galaxies. To be as far away as they are, given your proposed timescale, they would be unexplainable given all our current knowledge. They simply couldn't possibly travel that fast. Maybe they were made like that? You want to tear away all accepted science for your baseless premise? Science is always ready to be turned on its head, but better evidence is required. Observing these galaxies is thebasis for most predictions of age. We can tell how fast they are moving away from us, due to the joys of red shift (doppler).

    2. Craters. That fucking huge crater in America (name escapes me, it's late here in the UK). If it were recent, within a few thousand years, life wouldn't exist. The dust possibly wouldn't have even settled yet. The GMST would be near zero. (Combined effect of end of ice age and sunlight blocked out by dust, resulting in MORE ice forming, resulting in MORE sunlight being reflected rather than absorbed) Maybe the crater was made too? Maybe all the fucking huge craters on earth that invalidate your theory were made?

    3. Cave paintings (France, also Aboriginal painting in Australia). Located in places where they have been well preserved. Accurately dated to have been made before the universe existed, according to you. Maybe all dating technology is hopelessly inaccurate? If so, your comet theory is thrown out also. Did your 'Creator' paint on cave walls? Blueprints, perhaps.

    To the loony bin with you.
  • The makers of Zero Wing should have hired you.
  • Could you provide pointers to some of that "lots of evidence"?
  • Will someone, ANYONE, explain to me what this 'all your [something] are belong to us' phrase, that everyone seems to find so funny, means?

    That is, if it actually means anything?

  • Sure ... that was the Chinxulub event. The crater and ripples are still visible (mostly via satellite imagery) in the Yucutan peninsula and Gulf of Mexico
  • Actually, it would be more appropriate "better" == "more fit to reproduce".

    --

  • This affirmation of yours ("atheism = religion") has been debunked so many times, it's not even funny.

    --

  • ironic, since comets are also thought to be the source of the complex organic molecules that eventually assembled into life in the first place.

    Probably all delivered in one big hunk....WHAM!

  • If it weren't for metamod, I'd abuse "informative" and "insightful" moderations for just this purpose.
  • "Better" is a value judgement that has no place in discussions of evolution.

    I thought that one of the main points of evolution was that "Better" == "more fit to survive". Is this wrong?

  • actually, they aren't so sure whether the later dinosaurs were all cold blooded (wish i had a link)

    -
  • > The truth is that lots of evidence suggests that the universe is very young, on the order of less than 10,000 years old.

    No way, man. 10Kyears isn't nearly long enough to explain the divergence between homo sapiens and homo trollens.

    --
  • It almost hurts to explain it, as I'm sure it destroys half the humor. Oh well.

    A long time ago there was released upon the earth a not-very-good side-scrolling game for a Sega system (genesis? master drive? whatever?) called "Zero Wing." Its intro sequence was horribly translated, including such gems as:

    "Someone set up us the bomb"
    "All your base are belong to us"
    "You have no chance to survive make your time"
    and
    "For great justice!"

    Now, the gaming community being what it is, there are a number of people who "collect" oddities like this. For some unknown reason, this one caught on to an incredible degree (much more than other bad translations, like "A winner is you").

    I personally think the real popularity began in the Something Awful forums -- but I could be wrong. From there, it spread to other forums, and was used quite a bit by Stile, of the famous Stile Project. Folks began modifying images using photoshop, placing the phrase in ads, and famous net photos. It's a huge in-joke that's gotten so big it's amazing.

    Now, it has a life of its own. Do a google search on the phrase; you'll be astounded. Look at mp3.com for a song inspired by it (Invasion of the Gabber Robots is the name, I believe). Pure genius. Somewhere out there someone put together a collage of shots from the original game and modified images, set it to the afore-mentioned MP3, and made a movie out of it. And it's damned funny.

    -Take off every 'zig'!

  • What have you been smoking?
  • The theory of natural selection doesn't suggest that bacteria are the pinnacle of evolution. It doesn't include value judgements of any kind.

    If you want to go around claiming that bacteria are the "pinnacle of creation" because there are more of them living in more diverse environments, that is your business, but don't pretend Darwin is on your side.
    ---
  • Radiolarians yes, fishes no. The fishes did not get started until the ordovician, and did not become important until the silurian ( aka the age of the fishes).
  • Someone out there must have some ideas. Is it really possible to divert a planetary collision of the kind of magnitude that destroyed the dinosaurs? Or are we doomed if it ever happens (this of course assumes that humans are still around and aren't slaves for those damn dirty apes)

    -----
    No the game never ends when your whole world depends

  • Actually, there are many "largest" extinction periods in earths history. Its a subjective matter in which you have to take into acount the number of species involved and the duration of the event. Perhaps the biggest would be the anarobic extinction caused by the saturation of the oceans and the atmosphere with O2. Most anarobic life was killed off and replaced with arobic life. That happend way back (1.5 billion yrs?) and it is impossible to accurately say whether it was 95 to 99% of species killed.
  • One KILOGRAM per YEAR ?!? Your estimate is very low, I believe the earth gathers many TONS per DAY, all in cosmic dust and micrometeorites. And even at that rate, that represents a very very tiny percentage of the earth's total mass.
  • The comet in the artists conception is a little larger than 7 miles across...
  • The question would be, in this case, whether or not this can be considered part of the normal evolutionary process.

    To say that a mass extinction is normal would be stretching the point. Having conditions suddenly become very hostile will allow for rapid evolution. Rapid evolution should lead also to rapid specialization. I believe there are some interesting studies about life AFTER these mass extinctions and how there is a proliferation of new different species.

    Think about it. If the Earth suddenly became alot more hostile, alot of the "weaker" species would die. ("Weaker" in quotes because certain conditions would favor some species more than other. It's not necessarily that one species is better. But I digress.) This would certainly qualify as an acceleration of the evolution process.

  • It was the Charonians! They killed the dinosaurs. ;)
  • Right you are. And as a matter of fact, all discontinuities between geologic eras/periods/epochs are mass extinctions of varying magnitude. After all, thats what the different strata were named for originally; their fossil content. A sharp discontinuity and you use another name, e.g. Triassic-Jurassic-Cretaceous...

    The primary division is between eras: Precambrian, Paleozoic, Mesozoic and Cenozoic, with as you might expect big extinctions between. The Pracambrian-Paleozoic (or Proterozoic-Cambrian if you wish) the biggest, the Paleozoic-Mesozoic (Permian-Triassic) not quite as big but still incredible, and the most famous one, the Mesozoic-Cenozoic (Cretaceous-Tertiary) that killed the dinosaurs, the smallest of those three.

    In between there were smaller mass extinctions between geological periods; e.g Jurassic-Cretaceous or even smaller between epochs, like for instance Miocene-Pliocene. All mass extinctions were not necessarily caused by comet/asteroid impacts, directly or indirectly. Large igneous provinces (flood basalt) are another option, as are large climate fluctuations caused by continental drift.

    /Dervak

  • And BTW, any alien geologists examining the rock strata of the Earth in, say, 100 million years will find a very pronounced and extremely fast mass extinction right at the current time. Lots of animal and plant species disappearing in a very short time, especially big ones and predators, but many smaller species too.

    The rocks will contain a significant portion of carbon, that is, soot, and many heavy metals (probably buckyballs too). It is likely the aliens will put it down to an impact from space, but the big crater is strangely missing...

    /Dervak

  • No. The overwhelming plethora of evidence for a meteor strike around the time the dinosaurs died out is what makes it the generally accepted explanation.

    -Legion

  • 1. I won't forget that experiment, because if it had actually increased the speed of light, it would have been the first time ever, *anywhere*, where that phenomenon was observed. According to Einstein's theories of relativity, the speed of light in a vacuum is a constant; gasses and solids might slow it down, but *absolutely nothing* in nature is capable of speeding it up. Einstein's theories are among the most successful ever proposed to describe the universe--do you have a competing theory that includes all of his predictions, his models of time/space, and which also includes a model for your "but light can surely be sped up!" idea? If so, please forward it to Science for peer review.

    3. I know it is accurate for older items because: a.) decay rates are well known from direct observation, and b.) as another poster mentioned in this very thread, several other dating methods corroborate radiometric dating quite well. When you see three or four different dating methods all agreeing on the age of an object, do you dismiss them all as flawed?

    And saying we had ice age, then stone age, then this age & that still doesn't tell you the exact happenings to each specific artifact, nor can it ever!

    Well, you can argue that all you want, but it's not what we were talking about.

    -Legion

  • If, as you say, the word "day" has the literal meaning of a "day," then that would mean the Bible is utterly wrong on the topic of dates--we know that the universe is much, much older than the Bible claims. See other threads for discussion.

    -Legion

  • Well now, that would mean that the first part of the bible, as translated, is wrong.

    You have no idea how much that pleases me.

    -Legion

  • I take that about as seriously as I take your Bible's "evidence": "Moses parted the sea, no, really, I saw it myself, d00d!@#"

    -Legion

  • 1. Light is slowed under very specific conditions; if the light from other galaxies is traveling to us more slowly than usual, then they are even *farther* away than estimated, which would make the universe even older. The speed of light was never sped up--you seem to be confused as to what actually happened in that experiment.

    3. Carbon dating is only shaky when used to date fairly "recent" (geologically speaking) items. It is quite accurate for older items. Or are you implying that your god made the cave paintings look old just to fool us poor stupid humans?

    And unless any of you know of dinosaurs or people living here millions of years ago with cowboy boots on, I'm pretty sure that shoots down the dating process pretty well. I think I shall have to talk to that friend & figure out where he got this info.

    Presumably he found it in his ass or on Art Bell's website.

    -Legion

  • Good post, Dave, but I don't think you stressed it enough:

    In fact, all the evidence tells us that it is billions of years old.

    I'm going to get modded down for redundancy, I can feel it.

    -Legion

  • I think it's:

    "Mom, Dad... Don't touch it... It's EVIL!!!"
  • A Heinlien story, all life keeps getting wiped out and restarting tell we learn to move on to other planets. either intelligence wipes itself out or nature, but the whole struggle is just to learn to spread to other planets. but try explaining that to a politician
    1. ugh
  • Probably in 'The Dinosaur Heresies' by Ken Bakke (a great book, guarenteed to bring the 8-year-old in all of us). He did buckets of analysis on pedator-prey ratios and other ecology-type stuff and concluded that dinosaurs were in a moderately rapid decline before the comet hit. Another of his main points was that smaller, less mobile critters seemed to survive better than big, wide ranging critters in general, just the the opposite of what you expect if massive, sudden climate changes were the killer. He leaned more towards new infectious diseases encountered by the dinos as the moved from landmass to landmass over newly created landbridges as the killer. I'm hardly qualified to argue with him, but one thing I got from my BS in biology and 3 years of grad school was that very few things happen for only one reason, so if the dinos are running around gettings exposed to new pathogens while trying to avoid lots of geological activity and the effects of a big-ass comet strike, it's retty hard to point a finger and say 'This is the killer'.
  • Well, it sounds like you're saying (chance to protect) != (guaranteed survival).

    So how do you know that earlier species didn't have the same (or better) chances, but also failed to survive for some reason? The fact is, we really have no clear idea of the state of trilobite or dinosaur technology.

    Not to mention Lovecraft's accounts of advanced civilzations preceeding the Trilobites!

  • I`m sure i`ve read somewhere that dinosaurs started to die out before such an impact.
  • http://www.earthpulse.com/haarp/background.html
  • Talking of fish, i always find it funny that people always say `we evolved from apes`. Well, no we didnt - we evolved from single celled organisms, into fish, up through apes to what we now call Humans.
    Saying humans came from apes is like saying toast is made out of bread.
  • " Better" == "more fit to survive". "

    Yep, survival of those more suited for survival. Thats that cleared up :)
  • "Furthermore, Darwin specifically pointed out that by "survival of the fittest" he meant "survival of those most suited to the environment"" It seems that the famous Darwin quote has made its way into everyday vernacular as to insinuate a premeditated competition. So, you are fighting an uphill battle I gave up on.
  • I'm no astrochemist, so could someone tell me how they can be so sure that these isotopes were created from carbon stars that they can be used as evidence?
    --
  • we're in this band
    we ain't got no mic stand
    our music isn't that bland
    and, we play punk
    none of us can dunk
    all other muse is junk
    that's why we're Bucky Balls the band
    we'll never sell out
    that's not what we're about
    we play what we want to play
    so if ya don't like it
    just go away
    or just stay
    that's why we're Bucky Balls the Band
    Mike, Cameron, Corey
    Matt & Brad
    our music don't make ya sad
    and our music is really loud
    there usually ain't no crowd
    and
    that's why we're Bucky Balls the band


  • Perhaps. Or perhaps some terrestial process forms buckyballs and perhaps buckyballs preferentially absorb HE3. Buckyballs were only identified 10 years ago and there's a heck of lot that we don't know about them.

    The other unanswered question is where is the iridium? The KT layer is loaded with iridium which was one of the signposts of an extra-terrestial delivery that ended the Cretacious. The Permian event doesn't have any iridium associated with it. Iridium dust is presumed to be abundant in space and rare on earth.

    It may be that the hypothetical Permian asteroid was iridium poor and buckyball rich but it's going to take more than HE3 rich buckyballs to make a convincing case.

  • T-shirts aside, it is becoming more and more obvious, though new discoveries and theories that comet/meteor impacts have had a much more influence on the development of life here on earth and than just the one that killed the dinosaurs. This is a real and dangerous threat to our world. Sure, the odds are high, but so are the stakes. It is time that we, as a world of people concerned for it's preservation, start to cooperate. It's time we begin to plan and lay the foundation for the the assurance of the survival of our species. There are some really good efforts out there now, but those are just the beginning.

    There is a new computer-telescope system that is capable of using sensitive light detectors and detection algorithims that have proven effective at finding and tracking asteroids. I can't remember what the system is called but I know they have one installed and are planning a few more. This is good, it's a good first step. Perhaps a next step is a network of these around the globe that can constantly scan the sky in all directions. That sounds feasable even in the short term. Then we can ask "What is next?"

    Ok, we have our network of "eyes" and can see the potential doomsday rocks coming. What's the next step? One option would be to come up with a plan to deal with the threating asteroids or comets on a size and reaction-time basis. (send a team of oil-rig workers?? launch nukes?? use solar sails?? build large ground based repulsor beams?? build starships with photons torpedos??) Another option is to plan a survival strategy. (dig caves?? colonize the moon and/or Mars?? build large-scale space stations??) Yet another option could be working on a next generation of detection capability to increast the amount of warning time. (invent large powerful scannars?? "scanning...indications negative at this time." use intelligent meandering robot probes??)

    Anyway... we can pick an option or combination of options and set a large scale, long term plan into motion....a human preservation and defence initiative. Who knows how much time we have? We should not procrastinate on this issue. The stakes are too high.

  • well, in just today we've gotten tons of evidence supporting all sorts of fun things (like darwinism). GO DARWIN!
  • Well, I think god hates them on an entirely different level.

    --
  • God must really hate people who live near plate faults and active volcanoes.

    --
  • How does it go???

    laaa da de daaa...

    ...a question of origin...only in the recent past seekers fought to realize.....

    A ? of Origin....

    10,000 Millions speak toward the westward light, ......

    Secrets of Science the future is surely made....

    Our Home is Our WORLD.

    www.homeworld.com

  • I don't understand why people keep seeing God in everything.

    The same reason everyone around you starts using that new word you just learned. It's not that they didn't use that word before, it's only because it is fresh in your mind that you take notice of it.

    I think that people who see God's hand in everything tend to be very religious. If you are constantly thinking about God, you are bound to look at things with the perspective that He created everything. You are most likely to interpret a "coincedence" as God's presence.

    Likewise, if you think religion is junk, you're going to take more notice of scientific studyies that support your opinion. If someone presents evidence that they claim proves that God exists, you are going to try to find an explanation that doesn't require the existence of God.

    A lot of people are so intent on getting their point across that they don't stop to consider alternate explanations. They see things through the filter of what they believe and have experienced and find it unbelievable that someone else could disagree with them in light of the facts they've presented. We tend to believe and remember the evidence that supports our beliefs, and we tend to minimize and forget explanations and evidence to the contrary.

    (It's too bad things don't work that way with insults and compliments. Everyone seems to remember my insults and forget the compliments. You'd think they'd want to focus on the positive. :)

  • Mother Nature (as an iconic representation of the big bad universe) IS a bitch.

    You sir(or madam), need a little hubris. Flood, Famine Earthquake, all can destroy us in less than a geological eye blink. The energies released in the average hurricane are immense, the energies involved in a large meteor impact are beyond comprehension. Yes, one can talk of so many megatons tnt equivalent, that does not mean one can understand what that really means. Nature aside, we have existed for a tiny fragment of the history of life and have proven ourselves to be the greatest threat to our continued existance.

    Given the complete lack of political interest in practical space exploration, its going to be a couple of hundred years before we get even a tiny fraction of the species off this rock. Even then, that may simply be the catalyst to destroy the earth, since once we are in space, the earth based population becomes more expendable.

    But then, I am a pessimist.

    ;)

  • "All your base are belong to us" comes from the (bad!) translation of the opening sequence of an arcade game called Zero Wing

    The opening sequence of the game is as follows:

    In A.D. 2101

    War was beginning.

    Captain: What happen ?

    Mechanic: Somebody set up us the bomb.

    Operator: We get signal.

    Captain: What !

    Operator: Main screen turn on.

    Captain: It's You !!

    Cats: How are you gentlemen !!

    Cats: All your base are belong to us.

    Cats: You are on the way to destruction.

    Captain: What you say !!

    Cats: You have no chance to survive make your time.

    Cats: HA HA HA HA ....

    Captain: Take off every 'zig' !!

    Captain: You know what you doing.

    Captain: Move 'zig'.

    Captain: For great justice.

    Cats is the enemy and a "zig" is the fighter that you use in the game. Go to http://www.planetstarseige.com/allyourbase/ for more information.

  • Wow! How fortunate! I was afraid that with the fictitious war over we would stop spending so much money on defense.

    If we have six minutes (or even six months)to work with, I'll trust statistics more than a patriot missile.

  • heh, who says they'll be T shirts? Maybe they'll be W hirts or something by then - the dominant species might not have two arms and a head!
  • it and wiped out most of the life on earth, including the trilobites.

    Unfortunately, the tribble, a distant cousin of the trilobite, survived the impact and is now multiplying at a phenominal rate. Scientists predict that Earth's days are numbered. If we don't die from an asteroid, scientists say, the tribbles will take all of our food, water, and air supplies. Mankind's reign as kings of the world are over. Long live the tribble!

    --
  • 'i saw the end of the world and all i got was this lousy t-shirt'

    eudas

    p.s. the lameness filter sucks.

    eudas
  • then all of a suddon, bang... oops, now there aren't any windows

    That's because Windows sux.

  • That doesn't necassarily mean the evolved creatures would be any smart does it? I mean, they didn't really need any intelligence to survive, they just had to be hardier creatures that could survive extreme climates. Look at insects... They are highly evolved creatures and there are trillions in every possible environment imaginable on this planet. But does this mean they are intelligent?

    Wouldn't *intelligent* creatures that were more than likely not "as suited" for extreme environments been likely to evolve into an intellectual species sooner, had there not been any cataclysmic events that wiped them out?

    Very interesting though, Thanks for the insight.

    (PS. I'm asking a question! Give your thoughts, not a flame war!)
  • Radiocarbon dating also isn't the only dating scheme. It works quite a ways back, but you can also cross-reference it with "dendrochronology". It requires trees in certain conditions, but when you can do it, you can get dates down to the year. For really old stuff, you can use potassium-argon dating, which watches the decay of an isotope of potassium into argon. Scientists who do this junk don't usually settle for one line of evidence to give them a date. They apply as many methods as possible to increase their certainty in the value.
  • ironic, since comets are also thought to be the source of the complex organic molecules that eventually assembled into life in the first place. See amara.com [tass-survey.org] for a layman's introduction to the cosmic dust that comprise comets, and space.com [space.com] for a discussion of the possible link to life.
  • This article got me thinking about a conversation about hill climbing that I was having yesterday...

    For those of you without CS backgrounds, hill climbing is a general strategy for finding a solution to a problem. You basically characterize the problem in terms of a set of variables that define a multi-dimensional "surface", then define some function that maps these variables to a "goodness" value. Then you tell the computer to "climb the hill" until it finds the maximum (i.e. best) solution.

    Of course, the problem is that you reach local maxima--locations that are peaks, but not the highest peak. So what do you do? You can do a random restart, where you start in a new location and start climbing again, then compare the new peak to the old. Another thing you can do is perturb the existing path a little and start climbing in a new direction.

    Now, what if life on earth is a big hill-climbing experiment run by mice? The mice were unhappy with the simple ocean-dominated life of the Permian period, so they arranged to have a "random restart" in the form of a meteorite. Then they weren't happy with the dinosaurs in the Cretaceous period, so another meteorite.

    Now, we've been giving mice AIDS and cancer for years. And we've been squishing them in mousetraps as part of a concerted effort to eradicate them. How long before they decide it's time for another restart?

    [Apologies to Douglas Adams...]
    --------------------------------------- ----------------

  • I used to be a firm believer that the major extinctions were caused by impacts. Then I read Vincent Courtillot's Evolutionary Catastrohes [dannyreviews.com] and now I'm not so sure. That book makes the case for volcanism as the explanation of the seven major extinctions.

    Danny.

  • There is genetic variety evidence that some species
    appear to be descended from a very small population.
    Chetahs are one example, with all current individuals
    nearly clones of each other.
    Humans are another example, with evidence of an
    Adam/Eve population about 200,000 years ago of
    less than 10,000.

    These bottlenecks, such as caused by meteors,
    may drive rapid periods of evolution.
  • This discovery concerns the Permian extinction
    300 mya. Only fishies then. Lot fewer afterwards,
    The dinosaur extinction is 65 million years ago.
    The Snowball earth is 600 mya.

    There could be dozens of these catstropic events
    in Earth'd four billion years.
  • Nader voters will be unaffected however.
  • > coincidence != causation

    Maybe mass extinctions cause comet impacts.

    --
  • I have to ask - is the atmosphere actually boilng off?

    If we perform a mass balance around the exosphere, yes, meteors do rain down an contribute mass. But, does the earth "shed" a sufficient amount of gaseous matter to even things out a bit?

    If not, maybe we should just catapult old Buicks out of the exosphere?
  • As Darwin himself often pointed out, his theory of natural selection implied a general trend for later generations of creatures to be better suited to the environment of their ancestors (and thus to their own, assuming things hadn't changed much).

    "Better" is a value judgement that has no place in discussions of evolution.

    There is no "normal process of evolution". Some things die, some live, some reproduce, some don't; mutations occur, and either spread or disappear. Lifeforms today are different from lifeforms that were around a million years ago, due to these chance occurances. That's all there is to evolution.
    ---
  • To blow a huge gaping hole in every atheist's personal beliefs and theories:

    What if God and the Universe were literally the same thing?

    Think about it for a second.

    Rebuttal in advance: "So if God created the universe.. you're saying the universe created itself?" Maybe I am, maybe I'm not. Anybody who's ever studied the `big bang' realizes that the universe never actually was created, never actually started; time simply goes as far back as a certain point, and that's all there is. It's not like before that there was empty space; there *isn't* any "before that." It didn't exist!

    God could be lots of things. God could be number theory. God could be the laws of physics. Who is anybody to say that God has to be some majestic humanoid? "And God created man in His image." Image... who's to say image means physical image? Maybe it's why we're conscious and no other species appear to be.

    If God was the universe... then anything that anyone does, anything that anyone discovers by the scientific method, anything that happens to promote evolution and the big bang... would still be God.

    Try picturing all of time and space as a single instant in a higher dimension.

    If you're inside a vacuum, how do you know it's a vacuum? Because every environment pushes in on the walls, implying higher outer pressure? What if you went somewhere where the walls were pulled outwards?

    You can't know anything from inside the bubble, nor from outside the bubble, so don't pretend to.

    And a question to throw out there: So many scientific theories rely on general acceptance by the majority of the scientific community to be considered truth. These are often based on other widely-accepted postulates.

    Suppose that these theories and postulates are partially correct; correct for the majority of applications.

    What's 2/3 of 2/3 of 2/3 of 2/3? A majority of a majority of a majority of a majority, right? But that isn't a majority anymore... 16/81 is actually a pretty small fraction.

  • Buckyballs? Where did these come from?

    "Comet hits Glasgow ned creating isotope of Buckfast Tonic"

  • I wonder if any research has been done as to whether the evolutionary changes brought about by this impact had similar effects as the impact that killed the dinasours. Some researchers claim that without this impact, mammals would never have become the dominant life form on the planet. It would be interesting to see how this older impact may have affected lower level life. It's rather amazing that these impacts, at just the right time could be responsible for the develpment of life as we know it.
  • The oort cloud.

    --
  • We are the only species to ever inhabit Earth that has a chance to protect itself [209.58.177.220] against an event as catastrophic as a comet/meteor/asteroid slamming into the planet and ending life as we know it.

    However...

    Our species also uses its spare time to do things like this [goatse.cx], this [rotten.com], and even this [slashdot.org] so I wouldn't exactly get my hopes up if a comet was screaming our way...
  • Your grammar and capital letter use sux. What you meant to say was:
    All of your bases belong to us!!

    This has been going on for quite some time, and I hope that all you trolls and crap-flooders heed my words and correct your grammar in the future.

    Remember, just because you like to defecate all over slashdot, you can still sound intelligent while you do it.

  • Couldn't tell if you were serious, but anyway, that argument ignores the fact that the earth is really, really big.

    No, I'm not wrong. Yeah, the earth is really really big, but only a small change in the distance of the earth to the sun, comparatively, would mean radical changes in climate. All this crap I've read and seen about dinosaurs has supported the idea that areas they roamed were tropical. Now, account for the estimated spread of Pangea, the timeframe of dinosaur existance and where they had lived (consider the range of fossil finds) and assume there was some migration winter-summer, they had to be living (condsidering dietary needs and conditions for plants herbivores dined on) in a relatively tropical or moderate climate year around. Present assumptions are these creatures were not covered in fur with big deposits of fat to insulate them, depends upon this, too. Probably most relevant of all is the size of these damn beasts. Nothing approaches their size today. Did they take too long to grow to that size and bacterial/viral threats evolved too fast for them to evolutionarily counter? Or might the gravity have been just enough less?

    The point I'm driving at is Earth is _not_ the same size and orbit it was 250 million years ago. My posit of 1 KG of galactic jetsam washing up in the the atmosphere is, by any account, extremely conservative. How much does the earth gain each year, just in dust to tiny to see? In the change, just of the Earth's mass mass and adjusting its orbit I find problems not addressed. Just some big damn rock did it all. C'mon, think about it.

    --

  • Interesting thought, but as the atmosphere is mostly Nitrogen, and there's not many sources for that (or weren't until the auto came along) It would have been gone long ago. Hydrogen and oxygen can come out of the abundant water, but, again, with little to replace that, it would have gone, too.

    I wonder if the earth didn't lose it's spin at some point and reverse. Anything to support the idea that it's always been going the same 24 hour spin (counterclockwise looking down at the north pole) or is that just another big variable that's been ignored while people focus on rocks hurtling through the cosmos?

    Yeah, big fiery rocks raining down sounds exciting, but what if they were plopping down all along and not actually part of this species change?

    --

  • Spot on.
    I think that most people are used to seeing the *tree* of evolution that ends with humans at the top and assume that the whole point of the deal was to end up with us.

    Thats probably also the reason a lot of people don't like the theory. They just are not happy to find out that we are not the pinnacle of creation, that spot has to go to bacteria since they have been found (thriving) just about everywhere on and in the planet.

  • It's unfortunate that NASA amongst others are so eager to publicize this as a finding of the cause of the permian extinction. This wouldn't be the first time they've been prone to Time Magazine-like exaggeration.

    The scientists who've done this work have certainly done a good job in showing that there were interstellar asteroid collisions with the earth at that time which is interesting. However, there are also many other factors that could have played into the permian collapse (where an estimated 90% of species were eliminated), namely a tromendous amount of volcanic activity which I've heard would have been enough to bury the entire planet in 30ft of lava if it were spread evenly. As it is, the ash clouds could have blotted out the sky and killed plants, leaving animal species to wither. then again, there also could have been a fatal cross-species virus that wouldn't be detected in geological surveys. Who knows, really?

    As the scientists who've done this work themselves would be happy to point out, it's relatively easy to prove that asteroid collisions and the permian extinction were coincident when compared to the daunting task of proving it was a major cause, if a cause at all. As of now we have knowledge of a number of catastrophic occurences at the end of the permian era along with an extinction, but what's needed is evidence other than perjorative that links the two and describes to what extent each catastrophe was playing a role, if any.

    Just because the sun rises when I get up in the morning doesn't mean I make the sun rise by getting up in the morning.

  • The important thing to remember is that, like all disasters, extinction level events are the will of god. Ditto for that bit earlier today about evolution. Sure, it doesnt make sense, but I've been assured that everything is gods will. Really! I swear!

    the best part here is some people are going to take me seriously!
  • Something like this could happen to Earth again and we would have about 6 minutes warning at most. Nostradamus predicted that an asteroid would hit Earth in 2003. With sufficient money spend on space defense research, we could have something like a nuclear bomb that could destroy a comet or asteroid before it hits us.

    Hopefully the new Bush administration will increase the priority of this. Its a non-political issue really because it doesn't matter if you're Republican or Democrat when that big-assed asteroid hits you will be toast!

  • This theory was refuted in 1982 (from what I can rememeber) at about the same time that satellite images of the Yucatan Peninsula strengthened the hypothesis that a meteorite caused that (less severe) global extinction. I am incertain how good the online archives are on Scientific American but maybe somone else can chime in?
  • 1) comets come from the oort cloud located just outside the solar system. The oort cloud is full of fresh new Ice chuncks just waiting to be knocked toward the sun so they may become a comet.

    2)The moon is moving away from the earth at an infintesimal rate, and Yes if it was a constant rate then it would have been long gone; however there is a thing called physics(I know you Fundimentalists don't think that is true either).
    when the moon was closer to the earths gravity was much more powerful and while the centripital force of the moon pulled it away from the earth, the net force was actualy vary small, infact it was nearly non-existant. Over time the moon, with this small net force, began to move away from the earth, however, because of the small magnitude of the force, the moon moved at a much slower rate than it does today. therefore it could not have gotten any further from earth than it already is.

    btw, the moon is not the same age as the earth and the earth is not the same age as the universe. please don't try placing all three on the same time table like the bible does.
  • by TWR ( 16835 ) on Thursday February 22, 2001 @06:09PM (#409247)
    The article quotes one of the researchers saying that life has to adapt or die. In this case, does that indicate to us that the world is better for it in the end?

    Assuming that by "The world", you mean planet Earth, a mass extinction means absolutely nothing. Short of the eventual expansion of the Sun int a red giant (in about 4 billion years) The Earth is still going to be here, no matter what. Life, in some form, will survive, no matter what.

    Now, as a human being, I have a vested interest in human beings not going extinct. But I don't equate my personal interests with those of the planet.

    -jon

  • by kahuna720 ( 56586 ) on Thursday February 22, 2001 @05:38PM (#409248) Homepage
    was a frood who really knew where his towel was. Here's the Fuller FAQ [cjfearnley.com], as well as a coupla other [lilith-li.com] (+1; Informative) links [primalsense.com] to Bucky/Buckyball info...
  • by Sara Chan ( 138144 ) on Friday February 23, 2001 @02:17AM (#409249)
    If you go to the trouble of actually reading the story, you'll find the following:
    The [cometary] collision wasn't directly responsible for the extinction but rather triggered a series of events, such as massive volcanism....
    So the comet did not directly cause the extinctions.

    A likely scenario has been suggested by Hermann Burchard (at okstate.edu):

    In Permian/Triassic boundary strata in South China, the element iridium is not present or at most only in trace amounts.... This can be understood ... by noting certain connections with the iridium-rich Hawai'i hotspot, which has been moving in a SE direction across the Pacific for > 100Ma, probably 225Ma, starting off from Sibiria.

    As mentioned by Victor Clube and Bill Napier in their book "Cosmic Winter", magmas from the great Hawai'i volcanoes are rich in iridium. ... There is a clear trace on the floor of the Pacific ocean beginning with the Emperor Seamount chain from the Kamchatka Peninsula to Midway Island, then angling off in a slight left turn along the Hawai'ian island chain. Although the trace possibly is now partly subducted in the Kamchatka - Aleutian trench, it seems clear enough that the hotspot was originally positioned in Eastern Sibiria.

    Underlying the hotspot is a mantle plume which presumably was created when a cosmic body hit Sibiria and created the vast flood basalts of Yakutia (Sakha). See the article by Renne et al. in "Science", 1995, 269:1314, for a map of the conjectured extent of the original lava beds....

    Therefore, little doubt can exist concerning the essential identity of the following events:

    1. Inception of Hawai'i hotspot in Sibiria.
    2. Sibirian flood basalt eruption.
    3. Cause of P/T mass extinction.

    Event 1 probably was a cosmic body impacting in Sibiria....

    To summarize the above--a comet crashed into Earth, which triggered massive volcanism, which in turn led to extinctions.
  • by ackthpt ( 218170 ) on Thursday February 22, 2001 @06:48PM (#409250) Homepage Journal
    Yeah, well, I'm still puzzling over the fact that Earth has been accummulating mass all these years. Let's take that nice number, 250million. Life was just humming along, a dinosaur here, a Gary Larsonesque mammal there (writing Mammals Rule on a rock), a few trilobites gnawing away on whatever the heck trilobites gnaw away on. So space chucks this big rock at Earth -SPLAT- and it all cools down, those with winter coats or able to burrow make it, those who do it nekkid end up kicking the darwinian bucket. Ok... fine.

    Fast forward to today. Global warming, yada yada yada. Only, assume that only 1 kg of dust, meteorites, etc. per year fell to earth. So that's ..um.. 250 million Kg the earth picked up, not counting the odd rock bumping into the Yucatan or prehistoric Winslow, AZ. To maintain the same orbital period the earth has to move away from the Sun, or to maintain the same distance, it speeds up (conservation of momentum or Keppler or somthing anyway.)

    The way I see it, it sped up, the seasons got shorter, the dinosaurs couldn't deal with the fast pace of the comparatively modern world and gave way to those twitchy little mammals which could.

    --

  • by ackthpt ( 218170 ) on Thursday February 22, 2001 @05:46PM (#409251) Homepage Journal
    Rejected again, ah well, here's the link to the UW article [washington.edu] this all springs from.

    Nice article explaining [mindspring.com] what a Buckyball is.

    --

  • by derf77 ( 265283 ) on Thursday February 22, 2001 @05:37PM (#409252) Homepage
    I bet it'll happen again sometime. Maybe not in our lifetime, but it'll happen, and someone will be there to sell t-shirts.
  • by TheDullBlade ( 28998 ) on Thursday February 22, 2001 @07:04PM (#409253)
    Yes.

    The theory of natural selection is a theory about what happens in the physical world, not a philosophy about what is good.

    Furthermore, Darwin specifically pointed out that by "survival of the fittest" he meant "survival of those most suited to the environment". He never meant to imply any general statement about things becoming better able to survive in general, in new environments which the species has not been exposed to. This can happen, but it is a side effect of becoming more adapted to the environments the species has been exposed to.
    ---
  • By knowing the process by which elements are created in stars, the ratios of stable isotopes and the time it takes for the radioactive isotopes to decay, scientists can get a pretty clear picture of where the materials come from, what kind of star was involved, how long ago it may have dispersed the elements, etc. Its complex science but its very real. Becuase mass spectrometer machines are very sensitive, you can measure all of the abundances very accurately, then using a lot of computer time you can work your way back to the starting conditions.

    In answer to the question, you have to ask where are you going to get a lot of He/Ar (old stars) where carbon is abundant at a high enough density to create the Buckyballs, at a low enough temperature that it isn't destroyed in the stellar atmosphere, and mass outflow from the star to cause it to end up in comets -- q.e.d. Carbon stars.

  • by at_18 ( 224304 ) on Friday February 23, 2001 @12:47AM (#409255) Journal
    This written in a book 1000's of years old which means the people of the time couldn't have had the scientific facilities to know this themselves... Coincidence? I would think most with an OPEN mind & willing to find out for themselves wouldn't believe so.

    No, it's not a coincidence. And I think that you don't need ANY scientific "facilities" to discover that the 8th day is the first good one, it just takes a little experiment:
    - circumcize on the 1st day: lots of blood and a death child.
    - circumcize on the 2nd day: same thing happens.
    - 3rd day, etc.
    ....
    - 8th day: oh well, it works.
    I don't understand why people keep seeing God in everything.
  • by jabber01 ( 225154 ) on Friday February 23, 2001 @06:53AM (#409256)
    The extinction you refer to is also theorized to have been caused by the stagnation of the Earth's oceans. This is believed to have caused global algae blooms which wiped out virtually all life in the seas (which was all the life there was at the time.

    An even more interesting catastrophe is the collision with our then closest neighbor, which created the Moon. This planet, called Oberon IIRC, was supposedly located between the orbits of old Earth and Mars, and intersected the orbit of Earth.

    At one point, old Earth and Oberon grazed each other, liquefying most of both planets and spinning a lump of rock off into orbit. The lump became the moon. The Discovery Channel devoted most of their "What if we had no Moon" program to this theory.

    It is also speculated that the asteroid belt between Mars and Jupiter is the remnant of another such collision, where the planets involved did much more than graze each other.

    The REAL jabber has the /. user id: 13196

  • by DerKlempner ( 249063 ) on Thursday February 22, 2001 @07:18PM (#409257) Homepage
    According to this Space.com article [space.com], there would have been a bigger mass exinction that happened 600 to 700 million years ago, or 350 to 450 million years before the collision described in the article above, which would have killed about 95% of all life forms on the planet. Here's a short version of the Space.com article:
    In the 1960's, geologists were unable to explain the evidence of glacial deposits found in the rock strata of every continent, including those at sea level aroung the equator. Was it evidence that ice had covered the entire planet at one time (i.e. a "super ice age")? Continental drift could have been responsible as well. Plus, how could the Earth get so cold as to have ice sheets covering it entirely?
    A recent theory suggested that for every drop in global temperature there is an increase in surface snow and ice. As more snow and ice builds, more heat is reflected away, and it gets colder and colder. If ice glaciers had progressed as far as 30 degrees to the equator, a runaway ice age would have frozen the Earth completely. The massive cold snap would easily triggered an extinction like no other. The theory only had one problem, though: how did the Earth eventually thaw?
    According to modern-day geologists, the levels of CO2 in the air are directly related to volcanic activity (which puts it there) and global temperature. As volcanoes erupt, they give off CO2 which is washed back to the Earth via rain. In turn, this CO2 is deposited back into the oceans where it settles on the sea floor as carbonate sediment. It is reheated to liquid, then gas, and the process starts anew when it is ejected again by volcanic activity.
    If a frozen Earth was still geologically active (tectonic and volcanic action), all the CO2 thrown off my erupting volcanoes would have nowhere to go. As the amount of CO2 in the atmosphere rises, the global temperature rises as well. A few million years later, ice begins to melt, the water vaporates into rain where some of the CO2 is redeposited back onto the ice where the process is repeated. Complete thaw would be quick, happening in less than a couple of hundred years due to the excessive amounts of CO2.
    As with the Permian-Triassic Boundary event (the meteor/comet incident 250 million years ago) that triggered the evolutionary process of the rise of the dinosaurs, the great freeze of 600 million years ago also triggered its own evolutionary growth: the Cambrian explosion. The massive dip in population followed by millions of years of harsh environments would have favored the birth of many new forms of life.

"Protozoa are small, and bacteria are small, but viruses are smaller than the both put together."

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