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Space Science

'Hundreds of Worlds' in Milky Way 334

Posted by CmdrTaco
from the nothing-to-eat-there-but-roddenberries dept.
Raphael Emportu writes "BBC news is reporting that rocky planets, possibly with conditions suitable for life, may be more common than previously thought in our galaxy, a study has found. New evidence suggests more than half the Sun-like stars in the Milky Way could have similar planetary systems. There may also be hundreds of undiscovered worlds in outer parts of our Solar System, astronomers believe. Future studies of such worlds will radically alter our understanding of how planets are formed, they say."
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'Hundreds of Worlds' in Milky Way

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  • No shit. (Score:5, Insightful)

    by Anonymous Coward on Monday February 18, 2008 @09:09AM (#22462476)
    No shit that there are other planets like ours out there. The incomprehensibly massive scale of the universe dictates it to be true, statistically-speaking.

    Today, children receive next to no education in the field of astronomy. Were they to have a proper understanding of what lies beyond Pluto, they'd probably grow up to realize how silly it is to believe that there is only one planet like Earth.

    • Re: (Score:2, Redundant)

      by mrxak (727974)
      Yeah, "hundreds" seems like an understatement. There are uncountable trillions out there, millions in our own galaxy.
    • Re: (Score:2, Insightful)

      by Thanshin (1188877)

      No shit that there are other planets like ours out there. The incomprehensibly massive scale of the universe dictates it to be true, statistically-speaking.

      9 * 10^21 stars.

      It's big, but it's not so big.

      Imagine we discover:

      That the chance of a star to have planets is one in a million. Doesn't seem impossible, does it?

      The chance of a star with planets to have one at the correct distance (taking star heat in consideration) to be between 0 and 100 C, one in a billion.

      The chance of a planet in the correct position to have water. One in a million.

      So, we still have nine planets. Now, cross your fingers that one of those is not radioactive, doesn't show the same side

      • Re:No shit. (Score:5, Informative)

        by Yvanhoe (564877) on Monday February 18, 2008 @10:19AM (#22463224) Journal
        That the chance of a star to have planets is one in a million. Doesn't seem impossible, does it? The survey of the closest stars around our solar system seem to contradict this. I don't have exact numbers, but too many planets were discovered within a 50 light-years radius to conclude that only one star in a million has a planet.

        Of course the Earth could be located in a statistical anomaly within the Milky Way, but if you posit a uniform repartition of planets, there has to be more.

        I am just nit-picking however. I fully agree with the rest of your post.
        • Re: (Score:3, Insightful)

          by beckerist (985855)
          Maybe it's just me, but the formation of planets around their respective stars seems LOGICAL more than a statistical improbability. The universe is messy, and there's a LOT of extra junk kicked out during the formation of stars. That's not including all that stuff out there that's NOT glowing (though: not dark matter...I'm still talking normal matter here) that might be caught in the gravitational slings of their closest large neighbor.

          My point is: there's an awful lot that goes on in ANY system for us to
      • Re: bad guess (Score:5, Insightful)

        by Jeremy_Bee (1064620) on Monday February 18, 2008 @10:45AM (#22463512)
        I disagree. I understand the argument you are trying to make, but your "1 in a million" suggestions are really more akin to wild stabs at the biggest number you can think of, than they are reasonable guesses. 1:1000000 is really an unusually small ratio, and not as common as you intimate. It certainly has no actual relation to the situations that present themselves in the formula.

        You can't simply spout a bunch of hyperbole and expect to be taken seriously. Especially in reply to an article that attempts to actually determine those numbers and percentages based on facts. This kind of talk is really no different from the comedy statement that "90% of people know that you can prove anything with statistics." It's meaningless.

        While we will likely have to wait a whole lot longer for meaningful answers to the Drake equation, attempts at putting fact-based numbers on the variables should be applauded, and discounting them with what amounts to emotional hyperbole should be discouraged IMO.

        • by Thanshin (1188877)

          You can't simply spout a bunch of hyperbole and expect to be taken seriously. Especially in reply to an article that attempts to actually determine those numbers and percentages based on facts.
          Excuse me, but my reply was not to the article but to:

          "The incomprehensibly massive scale of the universe dictates it to be true, statistically-speaking."

          (Speaking of hyperbole and statistics jokes).

      • They are totally unreasonable in just about every sense. Learn some basic astronomy before pulling "calculations" out of your ass.
        • by Thanshin (1188877)

          They are totally unreasonable in just about every sense. Learn some basic astronomy before pulling "calculations" out of your ass.
          1 - I did state I was inventing the data.
          2 - I would be interested in your estimations.

      • Re:No shit. (Score:5, Insightful)

        by meringuoid (568297) on Monday February 18, 2008 @01:09PM (#22465406)

        Imagine we discover: That the chance of a star to have planets is one in a million. Doesn't seem impossible, does it? The chance of a star with planets to have one at the correct distance (taking star heat in consideration) to be between 0 and 100 C, one in a billion. The chance of a planet in the correct position to have water. One in a million.

        Point 1: very long odds, given the number of extrasolar planets we've already discovered.
        Point 2: extremely long odds. It's a reasonably wide zone for the Sun, from about halfway between Earth and Venus out to Mars - which would probably be inhabitable if it were larger and could hold a thick atmosphere. Moreover the zone will shift as the star evolves and brightens, so a planet that starts out frozen may spring to life in later years. Come the red giant phase even Titan might bear life.
        Point 3: totally redundant. It just repeats point 2, but for some reason does so with a probability greater by a factor of one thousand. Counting the same criterion twice just to get the numbers down by a factor of a million is cheating.

        So, we still have nine planets. Now, cross your fingers that one of those is not radioactive, doesn't show the same side to the star (that happens quite often), is big enough to have enough gravity to hold an atmosphere, etc.

        How do you know that tidally locked planets are commonplace? There are none in our system.

        • Re: (Score:3, Informative)

          How do you know that tidally locked planets are commonplace? There are none in our system.

          None, except for Venus...

          But yes, I agree most of the numbers seem like poor WAGs, and the water point seemed redundant.

        • Re: (Score:3, Informative)

          by HiThere (15173)
          Sorry, there are lots of tidally locked bodies in our system, Luna would be called a planet if we were at all objective. It's tidally locked (to Earth). Mercury is tidally locked...it's a resonant lock, but it's still a lock. And Mercury *IS* called a planet.

          Still, any planets that are tidally locked will be very close to some larger body. If they're close to the sun, then they'll be out of the liquid water zone. If they're close to something else, then I don't see why that should exclude them as a hom
      • Re: (Score:3, Insightful)

        by cruachan (113813)
        These are just ridiculous figures. To start with the chances of a star having planets now appear to be way way lower than one in a million, given the rate at which we keep finding them even with our primative technologies (273 to date, with an estimate of at least on in 10 stars having planets).

        Once you have planets the odds of one being in a reasonably correct orbit for liquid water would now appear to be quite good as latest evidence indicates that it seems planets form wherever they can. Even being cau
  • by Thanshin (1188877) on Monday February 18, 2008 @09:09AM (#22462482)
    Now, if we only had some means of reaching it...

    The speed of light is a barrier like few the humanity has ever found.
    • by khallow (566160)
      A far bigger barrier is to exist at all.
      • And to be intelligent on top of that.
        • by Thanshin (1188877) on Monday February 18, 2008 @09:39AM (#22462796)

          And to be intelligent on top of that.
          That barrier is so high that most humanity never got to surpass it.
        • by rucs_hack (784150) on Monday February 18, 2008 @09:46AM (#22462874)
          And have caek
        • by IndustrialComplex (975015) on Monday February 18, 2008 @09:50AM (#22462908)
          The probability for intelligence seems to me to be the biggest hurdle. That humans are intelligent at all seems nothing more than a genetic fluke, and not a guaranteed outcome.

          However, given our understanding for life, and how it evolved, it would seem that complex life forms would probably NOT be rare at all.

          The biggest hurdles for human-like intelligence probably includes the following:

          1. Self replicating molecules. I'm not sure how precise the conditions for getting life started are, but it probably isn't something we would see very often.
          2. Conditions remaining stable for those molecules for a very long time.
          3. Symbiotic relationships developing between organisms. (requirement for multi-cellular life)
          4. The creativity mutation. (for lack of a better term.)

          In between, it seems that the process of natural selection would be the driving factor, but those 4 items listed are probably the most important 'leaps'.

          With regard to the creativity mutation: As I recall, there was a proto-human homonid that DID use tools, but never developed on that tool (The stone axe they used at the beginning of their existance was the same stone axe that they used at the end of their existance) And that period of time wasn't short, something on the order of millions of years where they used the exact stone axe. While they were using a tool, there was no real thought behind it. In that respect, it seems that it was much like a spider's web, a very precise tool for survival but instinct rather than a developed idea.
          • That humans are intelligent at all seems nothing more than a genetic fluke, and not a guaranteed outcome.

            Given sufficient time, all things possible are inevitable.
            • by spun (1352) <`moc.oohay' `ta' `yranoituloverevol'> on Monday February 18, 2008 @11:21AM (#22464046) Journal
              Not necessarily. Look at Conway's life cellular automaton. There are many valid configurations within the game that can never be reached without setting it that way to begin with. They are called 'garden of eden' configurations. And given any particular starting configuration, there are plenty of configurations that won't ever be reached. And if you define 'possible' as 'any condition that can be reached from a given starting condition,' then you have constructed a tautology and have not said anything useful at all. You are basically defining possible as 'that which happens, given enough time.'

              Put another way, "given enough time, monkeys will fly out of my ass." Now, evolutionarily speaking, flying monkeys are possible. It is also possible, given enough mechanical force, that my ass could be stretched large enough to fit the wingspan of an average flying monkey. But I really doubt that even if you waited around for an eternity, you'd ever see a monkey fly out of my ass.
              • Re: (Score:3, Interesting)

                by thrillseeker (518224)
                There are many valid configurations within the game that can never be reached without setting it that way to begin with.

                Conway's Game of Life (which I remember programming on a ZX-80 computer, good grief) is an extremely limited set of rules compared to the Universe's - it specifically doesn't allow for randomness - all configurations of the game can be reached if the initial conditions are randomly set.

                For your viewing pleasure [ibiblio.org]...
          • by TripMaster Monkey (862126) on Monday February 18, 2008 @10:33AM (#22463390)
            With regard to the creativity mutation: As I recall, there was a proto-human homonid that DID use tools, but never developed on that tool (The stone axe they used at the beginning of their existance was the same stone axe that they used at the end of their existance) And that period of time wasn't short, something on the order of millions of years where they used the exact stone axe.

            I believe the specific hominid you are referring to is Homo Ergaster (Working Man).

            While they were using a tool, there was no real thought behind it. In that respect, it seems that it was much like a spider's web, a very precise tool for survival but instinct rather than a developed idea.

            I don't know if I agree with that assessment. It seems to me as if H. Ergaster simply progressed as far as his brain would allow, and no farther. A simple hand axe was just the apex of his ability. Looking at H. Ergaster makes me rather worried about the future of our species...after all, we haven't been around nearly as long. What if we run up against an innate limit in our brains, and our technology can proceed no further?
            • by Rogerborg (306625)
              It's OK, we're pretty close to handing the baton over to our new computer overlords. Look at Slashdot: they replaced their "editors" with shell scripts in 2004, and nobody noticed.
            • by IndustrialComplex (975015) on Monday February 18, 2008 @11:14AM (#22463958)
              I don't know if I agree with that assessment. It seems to me as if H. Ergaster simply progressed as far as his brain would allow, and no farther. A simple hand axe was just the apex of his ability. Looking at H. Ergaster makes me rather worried about the future of our species...after all, we haven't been around nearly as long. What if we run up against an innate limit in our brains, and our technology can proceed no further?


              I think that it helps illustrate what is actually a non-distinct separation between H. Ergaster (thanks for identifying that) and modern humans.

              If it were the case that H. Ergaster simply reached the limits of their mental capacity, we should have seen other examples of tool use. We should be able to find species which developed tools a step or two beyond H. Ergaster. Instead what we see is that there is a type of technological explosion beyond that point.

              I would argue that our intellect has reached a sort of 'critical mass' with regard to its capacity to manufacture tools of increasing complexity and advancement. While we may reach plateaus, our intellect allows us to circumvent artificial limits and develop new technologies. Even now, we are inventing tools that help us create tools that are beyond our physical limitations (CAD, genetic simulations, etc).

              In contrast, H. Ergaster invented and used the stone axe, and almost a half million years later was still using the same stone axe. In a similar amount of time, modern humans have progressed from the stone axe, to sending robotic explorers to other planets.
    • Re: (Score:3, Funny)

      by somersault (912633)
      It could be a bigger barrier getting everyone to stop playing Solar System of Warcraft long enough to get onboard the faster than light vessel... unless perhaps they have an exclusive SSoW expansion pack onboard the ship.. hmm..
    • Re: (Score:3, Insightful)

      by Mordaximus (566304)
      Not much bigger than the 'Earth is flat' barrier. It's only a matter of time before we reach the necessary level of understanding.
    • by microbox (704317) on Monday February 18, 2008 @09:44AM (#22462856)
      The speed of light is not a deal-breaker. It means that, from *our* perspective, we'll send people to distant planets and never hear from them again. But from their perspective, it may be a few years. If interstellar travel actually happens, then the speed of light issue is just a managable logistical issue. It means that space-farers must be able to think for themselves. They already must be self-sufficient in other respects.

      If there is a deal-breaker, then it is contruction and propulsion of such a craft. The vaster the craft, then the more unlikely it's construction. We might be able to fire ourselves off in a single direction, but how do we slow down, and what if we need to change course. If we need to come home, then we've doubled the energy required!

      Then there are complex issues with people - our fragile minds and bodies. How do we react to the stress of space-travel, can we do it?

      The speed of light seems like a comparatively simple issue.
      • Re: (Score:3, Interesting)

        by schiefaw (552727)
        Navigation may be an issue:

        Holly: Look, we're travelling faster than the speed of light. That means, by the time we see something, we've already passed through it. Even with an IQ of 6000, it's still brown trousers time.
    • Re: (Score:3, Interesting)

      by vertinox (846076)
      The speed of light is a barrier like few the humanity has ever found.

      Imagine if you would a cure to aging or a method to remain in stasis for hundreds or thousands of years. Once we get that out of the way, traveling to another solar system isn't that far fetched. It is suspect there is enough material in the vacuum of space between systems that could help refuel a fast traveling vessel to keep propulsion up and since there is no weather or space bacteria (that we know of) erosion and decay won't be much of
      • by Thanshin (1188877)

        if humans could at least travel close to the speed of light
        If humans could travel at speeds close to c, we wouldn't need to have immortality. The slowness of time would allow the travelers to reach the stars in a normal lifespan.
  • Not so Rare Earth (Score:5, Insightful)

    by sgbett (739519) <slashdot@remailer.org> on Monday February 18, 2008 @09:10AM (#22462484) Homepage
    Interesting, considering that just last night I was watching a documentary, on BBC4 no less, about rare earth theory and how miraculous it was that the conditions on earth are as they are.

    Funny but, I couldn't shake the feeling that the reason conditions here on earth are so 'perfect' for life as we know it was more to do with life as we know it evolving to fit the conditions ...
    • Re: (Score:3, Funny)

      Funny but, I couldn't shake the feeling that the reason conditions here on earth are so 'perfect' for life as we know it was more to do with life as we know it evolving to fit the conditions ...
      No, no! Can't you see? Earth is incredibly rare! Too rare to be a coincidence. Nope, must've been an Intelligent Designer that created life. Probably about 6,000 years or so ago. Yep.

      Heh. This new information kinda blows a hole in that theory, huh?
      • by Dunbal (464142) on Monday February 18, 2008 @09:37AM (#22462778)
        This new information kinda blows a hole in that theory, huh?

        Yes, but His Spaghettiness is most forgiving. May you be touched by His Noodly Appendage forever. Hang on, that sounds a bit like icky things Japanese do with tentacles... oh second thoughts...
      • Re: (Score:2, Funny)

        What a quaint and backward notion! There was no Intelligent Designer who created life [scoff], it was an Intelligent Astronomer who placed our planet in the perfect spot for life to form on its own. Of course, there are some indications that it was actually an Intelligent Particle Physicist who started it all off, so there are obviously many more discoveries to be made in the field of Intelligent Science.

        But an Intelligent Designer? Piffle! He just hung the drapes and painted the place. And the bast
    • Exactly, as well as the simple fact that if conditions weren't suitable for life here, there would be none of us here to remark on how suitable conditions are for life.

      An entire documentary based on a retarded truism. How depressing.
      • Re: (Score:3, Informative)

        by Dunbal (464142)
        Yes, this is known as the Anthropic Principle [wikipedia.org].
      • by tomhudson (43916)

        "Exactly, as well as the simple fact that if conditions weren't suitable for life here, there would be none of us here to remark on how suitable conditions are for life."

        Let me fix that for you: "Exactly, as well as the simple fact that if conditions weren't suitable for life here, there would be none of us here in our current form to remark on how suitable conditions are for life.

        If conditions were different, it doesn't mean that life (even intelligent life) wouldn't exist. Now let's all welcome our h

        • I didn't say 'if conditions were different'. I said 'if conditions weren't suitable for life'. If conditions were different, but still suitable enough for life, we would look different, but would still be waxing poetic about how marvelously well-suited this environment is for us.

          The OP nailed it - the conditions here are perfect for us because here is where we developed, evolving along the way to fit our conditions perfectly. There's nothing remarkable about it.
  • Wouldn't it be feasible that intelligent life could arise on a planet that is liquid? As long as the temperature of the liquid is sufficiently stable, there are sufficient chemical building blocks and there is not too much current, single cell organisms and then multi cell organisms could emerge.. Or am I wrong?

    Anyhow, cool to hear that being the third rock from the sun is nothing special.
    • Re: (Score:3, Insightful)

      by Ihlosi (895663)
      Wouldn't it be feasible that intelligent life could arise on a planet that is liquid?

      Complex life, certainly. Intelligent ... I'm not so sure, probably depends on your definition of intelligence. Complex social structures and communication ? Possible. Tool use ? I'd say that is less probable. In an aquatic environment, fins beat tool-compatible appendages any day.
      • Re:Aquatic life? (Score:5, Informative)

        by KokorHekkus (986906) on Monday February 18, 2008 @09:32AM (#22462724)
        Not every day or time, it all comes down to in which environment it has to survive. And we have examples of tool-compatible appendages in aquatic life here on earth: the octopus that can open plastic bottles http://www.youtube.com/watch?v=wfRqYjv9QgA [youtube.com]. And then there are other aqautic life that seems to do very well without fins such as crustaceans.
        • Octopuses are on my "Do not eat because they're too darned bright." list and have been there for awhile. I think uplift experiments involving them would be very interesting. :-)

        • i thought for sure that would be a link to sponge bob ...
        • I've heard the same thing, but I've also wondered that if they had longer lives and even more intelligence - would they be capable of moving on from where they are now? Perhaps they would develop some form of domestication and rationing of resources, but I don't see how it's possible for aquatic life to ever enter "the bronze age" since it's formidably difficult to light a fire under water...
          • Re: (Score:2, Interesting)

            by dissy (172727)

            but I don't see how it's possible for aquatic life to ever enter "the bronze age" since it's formidably difficult to light a fire under water...
            Yea, but just try telling that to the underwater volcanic vents!
      • While tool use is certainly probable in an aquatic species that evolved intelligence, I would doubt that any such species would progress past the stone age in terms of technology. However, they may evolve a very advanced society, afterall, the Ancient Egyptians and Mayan cultures also were just progressing out of the stone-age yet they had highly advanced societies.

        Why would they be limited to the stone age? If you assume that they are fully aquatic and not amphibian-like then they would lack one of the
        • by SQLGuru (980662)
          What about volcanic hot-spots? Seems like there would be enough heat there to do some smelting.....just like on the surface, the location and use of resources becomes the reason for wars.

          Layne
          • Without a doubt I think it would be a possiblity, but I'm not sure what changes would have to be made to the smelting process to produce something usable. While metallurgy isn't my area of expertise I can work through the process a bit to see where some problems would occur with an underwater smelting operation.

            It isn't sufficient to just have a heat source to smelt, if you just heat up the ore you would end up with melted ore. There is actually a chemical reaction taking place, mainly it is the use of ca
      • Re:Aquatic life? (Score:5, Insightful)

        by rijrunner (263757) on Monday February 18, 2008 @10:52AM (#22463624)

            Except, we are in the midst of people arguing about exactly how intelligent cephalopods and sea based mammals are.

            The truth of the matter is that we have no real way to gauge the intelligence of other alien life forms. Almost all tests are based on a set of assumptions. It is only fairly recently that we have even defined classes of intelligences within humans (Linguistic, Spatial, Musical, Body-Kinesthetic, Interpersonal, Intrapersonal, Logical/Mathematical). It is entirely possible that intelligent life could evolve in aquatic environments that score extremely high in multiple categories there and we would have no real way of knowing. We know that there are a number of species that have highly evolved linguistic characteristics. But, what are they saying? Is it "See Spot Run"? Is it something profound? Is it elaborate fart jokes? It is entirely possible that the social structures are subtle enough that we have no means of determining how complex they are. When whale song can be heard from thousands of miles away, how do you determine the society that hears it and responds and the relationship between the one singing and the ones listening?

            Someone once said that either we are alone, or we are not. Either answer is mind boggling.

            My view is that we don't even know if we alone here on Earth, much less the universe.
    • You're basically describing how life got started on earth.

      Sure, there are many others (http://en.wikipedia.org/wiki/Category:Origin_of_life), but I think that is the most commonly accepted one.
    • Re:Aquatic life? (Score:5, Insightful)

      by TripMaster Monkey (862126) on Monday February 18, 2008 @09:23AM (#22462638)
      Wouldn't it be feasible that intelligent life could arise on a planet that is liquid?

      Our own earthly cephalopods are pretty darned smart. Given the right conditions, it's not difficult to imagine a similar species attaining greater intelligence. Of course, such an intelligence, having developed in such an alien environment, would be radically different from ours. As Larry Niven says, there are brains out there that think just as well as yours...but differently.

      Also, although an aquatic species could conceivably develop intelligence, I can't imagine what form its technology would take. With such elementary things as fire denied to them, it's doubtful that they could progress to any reasonable level.
    • Re:Aquatic life? (Score:5, Interesting)

      by Dunbal (464142) on Monday February 18, 2008 @09:27AM (#22462674)
      As long as the temperature of the liquid is sufficiently stable, there are sufficient chemical building blocks and there is not too much current, single cell organisms and then multi cell organisms could emerge..

            Depends on how you define "intelligence". Our liquids are certainly teeming with intelligent life. Life itself apparently began in our oceans. Fish are certainly very smart - they feed themselves, find mates, defend territory, build defensive structures, some species live and travel in social groups, etc. These are all signs of "intelligence". Then if you want to cheat a bit and look at the ocean mammals - seals, porpoises, whales, these are extremely intelligent aquatic beings.

            Arthur C. Clarke, however, argued that CIVILIZATION, however, could not evolve in an aquatic environment, for the simple reason that you cannot have fire underwater. His interesting theory claims that fire, and our control of fire - has been a driving force in our technology. First the fire we would use for slash and burn agriculture - which while being devastating for the environment over the long term gave many short term advantages to the primitive farmer. Fire to make steam is what drove the industrial revolution. And that same power is still in use today, though we get our "fire" in the form of Uranium, or by burning fossil fuels. Then there is the "fire" from the sky - electricity. Harnessing this particular "fire" would be pretty tricky underwater.

            I guess it's an interesting concept to play with, and surely there are many possibilities that we biased, land dwelling humans could never dream of, but I respect Mr. Clarke and his idea. I think it would be difficult for an aquatic civilization to arise here or anywhere else.
      • Re:Aquatic life? (Score:5, Interesting)

        by Bender0x7D1 (536254) on Monday February 18, 2008 @09:46AM (#22462878)

        There are plenty of volcanoes under the water here on Earth. Could those serve as a source of fire?

        Perhaps primitive marine creatures would realize that some sort of algae-like food source grows better in the warmer waters around these "glowing liquid not-water" sources and start building walls around them to hold in that temperature. Sort of like farming - but with algae instead of regular "crops". This would give them a stable food source and they could get to thinking about other things.

      • Re:Aquatic life? (Score:4, Interesting)

        by Arccot (1115809) on Monday February 18, 2008 @11:07AM (#22463822)
        Arthur C. Clarke, however, argued that CIVILIZATION, however, could not evolve in an aquatic environment, for the simple reason that you cannot have fire underwater. His interesting theory claims that fire, and our control of fire - has been a driving force in our technology. First the fire we would use for slash and burn agriculture - which while being devastating for the environment over the long term gave many short term advantages to the primitive farmer. Fire to make steam is what drove the industrial revolution. And that same power is still in use today, though we get our "fire" in the form of Uranium, or by burning fossil fuels. Then there is the "fire" from the sky - electricity. Harnessing this particular "fire" would be pretty tricky underwater.

        I always thought that was a pretty uncreative comment from such a create fellow. If you eliminate the need to breathe (artificially) underwater, it's pretty easy to come up with a basic concept of civilization.

        Algae farms wouldn't be hard to manage with the most basic of technology. Power could be generated from currents turning water wheels. Heat based power sources could also work, such as sea floor hot spots or something using the differential between the warm sea surface and the cool sea bottom. Hard metals might be all but unworkable, but fabric and bone could be made easily with plant and animal life. That would then allow a relatively firm fabric based cage/pen for herding animals. Transportation obviously wouldn't be in the form of a locomotive, but perhaps a system of rapid current tunnels could be worked out. Or maybe the harnessing of larger sea animals.

        I don't know enough to determine the rest, but I think the rudimentary civilization is there; tool use, farming/herding instead of hunting/gathering, and the basics of transportation.
    • not very wrong (Score:4, Informative)

      by dominux (731134) on Monday February 18, 2008 @09:35AM (#22462750) Homepage
      a planet would not be 100% uniform liquid at room temperature. You don't get planet sized blobs of water. Our planet is a lot of liquid around a fairly small probably solid iron core. The most common liquid component of planet earth by a long way is magma. The solid rock crust and liquid water in the seas is so insignificant by comparison it is surprising we even bother to talk about it. Anyhow what you were probably thinking about is a planet with a surface completely covered by liquid water or something like it. I think something could arise on such a planet, at the surface (or possibly below it if we are allowed to assume a hot core with volcanic vents.) You could get algae mats forming and sinking when they die off. Huge floating mats could then provide an ecosystem for other things to evolve around. At some point there could be fishlike animals under the mats and amphibious creatures walking on top of the mats. I can't see any real limit to the size and stability of the floating mats. Any creature looking to develop technology would have to use organic materials, which makes electronics a bit tricky. In terms of leaving the planet, fuel and a launch pad wouldn't be too tricky, building the rocket might be though.
      • Re:not very wrong (Score:4, Interesting)

        by KillerBob (217953) on Monday February 18, 2008 @09:56AM (#22462978)
        From what I hear, our best chances of finding life in our solar system is Europa. It's a giant ice ball, but beneath a thin ice shelf, there's thought to be an ocean very similar to Earth's ocean in chemistry, that's about 100km deep. Other major possibilities include Mars and Venus, both of whom have environments we've already found can support some Earth-born forms of life. We suspect Mars may have supported multi-cellular life in the past, but Europa has the best chances of supporting it today.
        • Re:not very wrong (Score:4, Interesting)

          by TripMaster Monkey (862126) on Monday February 18, 2008 @10:02AM (#22463038)
          The problems with technology that regular aquatic races have would be even worse on Europa. Imagine an explorer trying to see what was beyond that great ice wall at the top of the world. After managing to chisel through miles of ice, the intrepid explorer would be rewarded with a quick death by blowout as the tunnel opened out onto the surface...in vacuum.

          I don't think we're going to be seeing many Europan astronauts anytime soon.
      • Re: (Score:3, Informative)

        by kels (9845)

        The most common liquid component of planet earth by a long way is magma. The solid rock crust and liquid water in the seas is so insignificant by comparison it is surprising we even bother to talk about it.

        The Earth's mantle is a crystalline solid, with only tiny isolated pockets of magma. There is no vast magma ocean. The lower mantle is subjected to pressures that can keep it solid well above 2000 degree C. Much of the mantle deforms over millions of years, but it is not liquid.

        The biggest liquid comp

    • by tomhudson (43916)

      Its been posited that life (including intelligent life) could be possible on the surface of a brown dwarf, using exotic chemistries, "helped along" by the much higher gravity. We just don't know, and we may never know.

  • by meringuoid (568297) on Monday February 18, 2008 @09:15AM (#22462544)
    ... there may be hundreds of worlds in the solar system. In the Milky Way, expect trillions. The distinction between the Solar System and the Galaxy is a subtle one, similar to that between a grain of sand and Saudi Arabia, so it's easy for the likes of the BBC to confuse the two.
    • ... there may be hundreds of worlds in the solar system. In the Milky Way, expect trillions. The distinction between the Solar System and the Galaxy is a subtle one, similar to that between a grain of sand and Saudi Arabia, so it's easy for the likes of the BBC to confuse the two.
      The TFA isn't confused at all, the summary on slashdot is though.
  • Drake Equation (Score:4, Interesting)

    by TripMaster Monkey (862126) on Monday February 18, 2008 @09:17AM (#22462558)
    Given hundreds of worlds within our own galaxy, if we apply the Drake Equation [wikipedia.org], there's a good chance that there's another intelligent species out there, although the chances of it being of a sufficient technological development to make its presence known is slim. Also, the 'accepted values' for the various parts of the Drake equation are subject to (sometimes intense) debate.

    This being said, given that most of these "nearby" worlds are tens of thousands of light-years away, with the current state of our technology, we might as well be alone.
    • Re: (Score:3, Funny)

      http://xkcd.com/384/ [xkcd.com] Sorry, couldn't help myself.
    • by wnknisely (51017)
      Right, and now the "Fermi Paradox" [wikipedia.org] suddenly become much more interesting. If there's a strong likelihood of other life out there, where in the heck are they? Why haven't they contacted us?
    • Re: (Score:3, Interesting)

      by bjorniac (836863)
      No. No it isn't. The Drake Equation is just a crock - it expresses something we have no data for in terms of a bunch of variables... that we have NO DATA FOR. People just guess the numbers and say "My God, there probably IS life out there!" But the fact remains that the numbers used in the Drake equations (at least some of them) are guesses. Maybe n_e is 0.01, or maybe it's 1/(#planets in universe).

      Using "Accepted values" for the Drake Equation are like using accepted values for the age of the earth taken f
  • ...planets, possibly with conditions suitable for life, may be more common than previously thought...
    I have heard this so many times that I'm losing track on how common we previously thought they were.
  • by Joe The Dragon (967727) on Monday February 18, 2008 @09:28AM (#22462676)
    so we can go to them?
  • If there are only hundreds of earthlike planets what are the extra Stargate addresses for?
  • by barzok (26681) on Monday February 18, 2008 @09:35AM (#22462752)
    except Europa. I'll not be attempting any landings there.
  • But do we want them? (Score:3, Interesting)

    by Chemisor (97276) * on Monday February 18, 2008 @09:58AM (#22463002)
    The question is whether we want to have any planets. From Earth, for example, you could construct 10000000 rotating hollow cylinders, 1000x1000km each, with reasonable gravity, perfect weather, safety from radiation, and sustainability for billions of years. The total usable area will be 1e11 square km, 196 times larger than the Earth. It is also portable and redundant, ensuring that the entire civilization is not wiped out by an asteroid. It can remain usable after the Sun burns out; you can install a fusion generator and mine Jupiter for fuel for a very very long time. So tell me again why we need a planet?
    • by mbone (558574)
      From Earth, for example, you could construct...

      Yeah, if you don't mind disassembling the whole planet. The NIMBY people would be all over you and, frankly, I would join them on this one.
      • Re: (Score:3, Informative)

        by Chemisor (97276)
        > Yeah, if you don't mind disassembling the whole planet.

        Why should you mind? I'm not necessarily talking about disassembling Earth. We could start with Venus and Mars.

        > The NIMBY people would be all over you and, frankly, I would join them on this one.

        Why? The planetoids will not be anywhere near your back yard. In fact, if you stay on Earth, you don't even need to be aware of their existence. They'll be so far, you will not even be able to see them without a huge telescope. And it isn't like you hav
        • by mbone (558574)
          The post didn't say "from Mars and Venus". It said, "from Earth," a planet in which I have some ownership rights.

          BTW, I think that Venus will be more terraformable than Mars.
          • by Chemisor (97276)
            > The post didn't say "from Mars and Venus". It said, "from Earth," a planet in which I have some ownership rights.

            Naturally, your ownership rights will transfer to one of the planetoids we build from it. I said we could start with Mars and Venus, but I'd consider it desirable to eventually disassemble Earth as well.

            In case you are wondering, living in the planetoid will not be any different than your present situation. You'll still have blue skies, rain and clouds, rivers and the sea. You'll be able to
    • Where are they going to bury you?
      • by Chemisor (97276)
        > Where are they going to bury you?

        In the same place as we ought to bury the ridiculous custom of burying people - in the recycler. That said, if you want a graveyard in your backyard on the planetoid, nothing would prevent you from doing it. It will have soil, you know. In my calculations I assumed a 100m shell, which is far deeper than you'd ever dig on Earth.
  • by mbone (558574) on Monday February 18, 2008 @10:06AM (#22463078)
    Apparently not, even at the BBC. What they were saying is that there could be hundreds of worlds in the solar system, not in the galaxy. (They meant in the Kuiper belt, far outside of Pluto and Neptune.)

    We have already found 273 extra-solar planets [obspm.fr] in the galaxy. No one doubts now that there are millions, if not billions, in the galaxy, and a puling "hundreds" of Earth type planets in the galaxy would strike most people following this research as a very low estimate.

    From the article : "Some astronomers believe there may be hundreds of small rocky bodies in the outer edges of our own Solar System, and perhaps even a handful of frozen Earth-sized worlds."

    I would also regard this as almost not news at all, given the rapid rate of discovery of TNOs [harvard.edu] (Trans Neptunian Objects), three of which so far are the size of Pluto or larger.
  • by Pedrito (94783) on Monday February 18, 2008 @11:09AM (#22463854) Homepage
    doesn't tell you a whole lot. What we do know is that most of the extrasolar systems we've found also tend to have Jupiter-like and larger planets and that in the majority of cases, these planets are either fairly close to their stars or in highly eccentric orbits. Either of these conditions would tend to make any "habitable" planets less habitable. A Jupiter-like or larger planet close in or in a highly eccentric orbit would tend to destablize the orbits of any small rocky planets in the habitable zone.

    There are so many things that have to come together to make our planet habitable, that I suspect these conditions are a lot less frequently found than a lot of people would hope. That's not to say I don't think is common in the universe. I do. I just think the vast majority (by several orders of magnitude) of it is going to be single-cell (or if not in the form of cells, of equivalent complexity). You need liquid water (which gives you a pretty narrow temperature range at any given pressure), you need something in the atmosphere to protect against stellar radiation (or, if it's a water planet, I suppose something in the water to protect), you need a planet that's active, but not overly active (and lots of factors go into that). Anyway, I suspect true earth-like planets are pretty rare.
    • by StikyPad (445176) on Monday February 18, 2008 @05:19PM (#22468318) Homepage
      most of the extrasolar systems we've found also tend to have Jupiter-like and larger planets and that in the majority of cases, these planets are either fairly close to their stars or in highly eccentric orbits.

      That's not an attribute of solar systems in general; it's an attribute of solar systems *we can detect* by viewing perturbations in a star's relative position. There's a reason the first planets have had extremely short orbits and extremely large mass. By virtue of the methodology, the larger the planet and the closer the orbit (which makes for a larger/faster wobble, respectively), the easier we can detect them. A planet with the mass of our Sun would still take centuries to detect with current technology if it had the orbital period of Pluto.

      Granted, you qualified your statement, but then you went on to describe the likelihood of an Earth-like planet based on our limited findings. That's a bit like saying "The faintest stars we can see with the naked eye are magnitude 4, therefore it's unlikely that many stars are dimmer than that."
  • by bigtimepie (947401) on Monday February 18, 2008 @11:40AM (#22464336)
    I know this is /., where science prevails. But I couldn't help a scripture coming to mind.

    Heb. 1: 2
    Hath in these last days spoken unto us by his Son, whom he hath appointed heir of all things, by whom also he made the worlds;

    I always found this verse interesting, using worlds as opposed to planets. So why wouldn't there be more than one?

    Just food for thought :)

  • the wonder (Score:3, Funny)

    by cpricejones (950353) on Monday February 18, 2008 @12:55PM (#22465256)
    Think of all the stargates ...

Hold on to the root.

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