Become a fan of Slashdot on Facebook

 



Forgot your password?
typodupeerror
×
Space Science

Planetary Formation Sim Suggests Many Water Worlds 85

StefanJ writes "Researchers at the University of Washington -- supported by the NASA's Astrobiology Institute, its Planetary Atmospheres program, and Intel -- have come up with a new simulation of planetary formation that suggests that not only are terrestrial planets (small, rocky worlds, as opposed to gas giants) are common, but that water worlds (the subset of terrestrials that have sufficient water to support Life As We Know It) may be plentiful as well. A key factor as to how 'wet' a planetary system's terrestrial worlds get: The eccentricity of the orbits of the system's jovian worlds. It will be a while before we have telescopes good enough to actually see terrestrial planets and spec out their atmospheric composition, allowing us to reality-check these simulations. But it's still cool to play with sims like this. I can't wait for the home version! (Emergency backup link to Science Daily article based on the press release.)"
This discussion has been archived. No new comments can be posted.

Planetary Formation Sim Suggests Many Water Worlds

Comments Filter:
  • So.. (Score:5, Funny)

    by hookedup ( 630460 ) on Wednesday December 17, 2003 @09:58AM (#7744813)
    Did the sim come with built in monsters/disasters?
  • Accuracy (Score:4, Insightful)

    by Slick_Snake ( 693760 ) on Wednesday December 17, 2003 @10:06AM (#7744873) Journal
    Given that we only have a small sample size to base simulations of world formations how accurate could this be. We have never seen an actual formation of planets and can only infer what happens. It amazes me how pompous we humans are in thinking we know everything. At one point we were sure the world was flat, that everything was made of four elements, and that lightning was thrown by a large man wearing a toga.

    Albert Einstein -
    Only two things are infinite, the universe and human stupidity, and I'm not sure about the former.

    • Re:Accuracy (Score:5, Insightful)

      by Scarblac ( 122480 ) <slashdot@gerlich.nl> on Wednesday December 17, 2003 @10:13AM (#7744955) Homepage

      - He said, on a web page that he connected to using a super-fast computer, built with loads of exotic materials like plastics we refine from dead dinosaurs, over a huge network of copper wires and glass fiber, etc etc. That you can post here is absolutely incredible.

      And yet we haven't seen a single electron. Ever. How accurate can our simulations be? This "electricity" thing can never work.

      • Re:Accuracy (Score:2, Informative)

        by BurritoJ ( 75275 )
        I take it from your post that you are unfamiliar with the computing term 'GIGO'?

        The only way to determine if the model is accurate is to check it against reality. All computer simulation for engineering and scientific work must be checked against experimental results to be validated before it is trusted as a predictive tool. Even after this verification, there are cases where it will be inaccurate and the educated and experienced user needs to be constantly aware of those limitations.

        However, if you bel
        • Asuming that I am Newton or Einstein and have a computer ... I can simulate the law of gravity as I know it fairly simple.

          Why do you think "I have to check against experimental results"?

          Experimental results(or simply observation of nature) are usually what drives finding the formular and thus leads to a simulation, and not other way around.

          Simulating the creation of a solar system is pretty easy, not many laws of physics are involved. Trying to observe and experiment is pretty hard, as the creation proce
          • hmmm... You're absolutely right. If you can't observe the phenomenon then the simulation is both simple and intrinsically correct and should be accepted as Holy Writ(tm).

            Seriously, the law of gravity is a model that has been observed and checked against experimental results. Just because it is accepted now, doesn't mean that it didn't go through the scientific process.
            Remedial Link [nau.edu]

            Notice how there is a big process between observation and 'Scientific Theory' that involves making a hypothesis (ie I
            • We are not talking about a theory here.
              We talk about a simulation.

              The usual way is: observation -> theory -> experiment/observation -> simulation.

              The original poster argued to go the opposite way, as he simpyl did not trust teh fact that "the creation of a solar system" can be simulated. And you more or less supporting his argument :-)

              angel'o'sphere
              • OOPS ... I ment more this:

                We are not talking about a theory here.
                We talk about a simulation.

                The usual way is: observation -> theory -> experiment/observation -> "succsessfull verification of the theroy" -> simulation.

                The original poster argued to go the opposite way, as he simply did not trust the fact that "the creation of a solar system" can be simulated. And you are more or less supporting his argument :-)

                Puh, less typos and a smal addition.

                And regarding this point of you:
                Oh, yeah... i
                • As a follow up to my comment, this page describes very good how the theories about solar system creation have evolved: http://www.physics.gmu.edu/classinfo/astr103/Cour s eNotes/ECText/ch11_txt.htm
                  I can not find a more accurate one in that short time ... I remember having read an article about that topic testing the distribution of asteroids, rock planets and gas planets depending on nebula size and creation process(heat, composition) when I was 16 ... 20 years ago.
                  angel'o'sphere
              • Hmmm... Allow me to clarify my position. I believe it is possible to simulate just about anything, assuming infinite resources & knowlege. However, just because a simulation has been written doesn't mean that it's accurate and just because it hasn't been verified doesn't mean that it's not accurate. My point is that until the simulation/prediction has been verified then we just don't know and should behave accordingly.

                I believe that the original poster was trying to argue that his hypothesis/theory
      • Re:Accuracy (Score:2, Informative)

        by Anonymous Coward
        And yet we haven't seen a single electron. Ever.
        Utter and complete tosh. We have had detectors sensitive enough to detect a single electron for decades. We have never yet had detectors sensitive enough to detect the abundance of water on a rocky world circling another star. Hell, we've never had detectors sensitive enough to detect the abundance of water on another rocky world circling this star!
      • Re:Accuracy (Score:2, Insightful)

        by Slick_Snake ( 693760 )
        There is one thing you are overlooking we can test our theories on electrons and refine them. When is the last time you went to a remote star to check and see if their number crunching predicted what is really there. Lots of data and lots of processing doesn't me squat unless the data is good and the theories are sound. I can take lots of numbers and manipulate them on 400 computers and conclude that "Barney the Purple Dinosaur" is really Osama Bin Ladin, but that doesn't mean that its true. Verificatio
      • Isn't this planet just the second most advanced computer to ever exist, even in the future? Wasn't it designed by mice for a TV show of which the purpose was to determine the ultimate question of life, the universe and everything? Isn't it ironic that just before a girl in a coffeeshop was to discover this question, and thus complete the quest of this supercomputer, that large yellow bulldozing ships will demolish the planet? Or is that another dimension?
    • Re:Accuracy (Score:3, Insightful)

      by RevAaron ( 125240 )
      What more do you have in science than inference from known data? What more do scientists have than making a conclusion from the data, having that conclusion challenged with new data and then forming something new?

      Sorry, but some of us aren't willing to just sit on our hands, isolating ourselves from the universe or our natural surroundings.

      Plenty of humanity is pompous, yes- including a lot of non-scientists. A real scientist may be pompous in his personal life, but in his view of science, no. Any scien
      • I believe he was referring to the fact that given we have only ever seen one solar system (sample size one) to infer much about other systems from it doesn't really shout simulation with confidence level 99%. Of course, I'm not sure that only data from this observed system was used in the sim (although I do not know what else they could have used). So I'm not sure his base assumption is any more valid than the one he complains about.
    • I'd be more worried about how all the necessary assumptions were made and unknown values decided. I think we have so little actual data on this issue, that you could make a simulation to support just about any hypothesis if you want to. I'm not implying there's any foul play involved here (such as getting funding for big interferometer to image extrasolar planets), because even if a human tries to be objective, he subconciously tends to make choices that lead to results he wants.
    • "We have never seen an actual formation of planets and can only infer what happens."

      That's why they used the term 'suggest' instead of 'prove'. I'm amazed you were modded up.
      • You honestly beleive that 44 simulations is enough to even suggest what the rest of the universe is like?
        One model and 44 simulations of that model does not give insight to anything but the one model. Think of the number of peramiters and you will relize how limited 44 simulations is. There is elements than there are simulations. Then you have to consider dispertion of them at "start" time, etc. etc. etc...
        This whole thing is one expensive guess, nothing more nothing less.
        • Re:Accuracy (Score:3, Insightful)

          by NanoGator ( 522640 )
          "This whole thing is one expensive guess, nothing more nothing less."

          If it's wrong, it's wrong. BFD. It's still an interpreted collection of data, and over time it'll improve. It's called science, and it's the basis of a lot of things you take for granted.

          Chill. Give the people working on it a little credit instead of trying to shoot it down because it's early in development.
        • Well,

          I just started my simulator. The condition is like this, a wooden table surface, a ice hockey puck placed on it about 20 cm away from the edge, and a raw egg on the ground.

          I conducted 44 times this experiment:
          Hitting the puck with varying impulse.

          Result:
          33 experiments showed that the puck wont slip over the edge of the table if the impulse is below 1kgm/s
          11 experiments showed that the puck slips over the edge and drops down to the ground if the impulse is above 1kgm/s

          From the 11 cases where the puc

        • > This whole thing is one expensive guess, nothing more nothing less.

          No, it's an informed guess.

          And there's a huge difference, as the past half millenium of progress in science and technology should let you know.

    • At least three of the four innermost, rocky planets in our own Solar System appear to have had sigificant amounts of water in the distant past. Earth has kept hers while Venus and Mars seem to have lost nearly all of their water. So, judging from our own Solar System water appears to be common. Now we have a planetary formation model which produces rocky worlds with water which we didn't have before.

      And why do you think this is not grounded in reality? Such a model should produce predictions of element abu
  • Ok. Was it just me? I could have sworn the article was going to be about SimEarth 2 from the headline.
  • "using" this sim (Score:4, Interesting)

    by RevAaron ( 125240 ) <revaaron@hotmail. c o m> on Wednesday December 17, 2003 @10:21AM (#7745040) Homepage
    you love sims like this? I find it pretty doubtful you've ever used a sim like this in any "home version." this isn't simfarm. it like doesn't have any snazzy openGL renderings of planets being born, one star system at a time, making a picture of the galaxy you can zoom around in by holding down the control- and meta-keys as modifiers of axis. It's a big and ugly number crunching beast that spits out some probabilities. fun, if you know what the numbers mean, but mostly worthless to an outsider.

    though i suppose someone could write a GUI front end that just takes the probability matrix it spits out and generate a random solar system based on the numbers, along with total mass, etc etc. But I could do that now with some guesses at the numbers and it wouldn't be much different...
    • Re:"using" this sim (Score:3, Interesting)

      by Urkki ( 668283 )
      Actually I believe it really simulates actual star system formation (44 different simulations, according to the article). It should be relatively easy to create snappy 3D animations of each of those 44 simulations you could zoom around to your heart's content.

      Of course that still doesn't make a sim-style game since after initial parameters are set there's nothing to *do*, just let the simulation run and see how the system develops.

      Hmm, sounds a lot like Stair and Truck Dismount [jet.ro] games, so perhaps it'd sti
    • You, sir, are a naysaying, party-pooping wet blanket!
    • 'I find it pretty doubtful you've ever used a sim like this in any "home version."'

      The daunting academic sims of yesteryear are the playthings of tomorrow.

      Ever hear of ACCRETE? It was a very early (early 70s) I first read about it in an old Carl Sagan book. It blew my mind! I remember staring lovingly at the sample outputs in _The Cosmic Connection_ and wishing there were more. Ten years later, I was RUNNING ACCRETE on my home computer!

      "Games" like Sim Life and Sim Earth would have been considered seriou
    • Let's use it for games!

      It'd be fun in, say, a space strategy game to be able to create a realistic solar system from a random number seed. Now, presumably these simulations were run on a supercomputer and took hundreds of CPU hours to do... However, I'm guessing that if you do enough runs, you can look at the numbers and come up with a simple algorithm that would give fairly reasonable results. Honestly, I'd love to get my hands on their data, even if it does look like a spreadsheet.
  • From the article: "It currently is impossible to detect Earthlike planets around other stars."

    As I am not overly familiar with astronomy, why is this the case?
    • by posa ( 677461 ) on Wednesday December 17, 2003 @10:51AM (#7745344)
      They look at the movement if the star then looking for planets. A "earthlike" planet is to small to move the star a detectable distance.
    • theyre hard to see through any telescope, radio or optical because of the aura the stars give off.. theyre so bright that they 'engulf' the planets and make them too hard to see... .equally, the planets dont reflect enough light to be visible enough.......

      it's changing slowly and i for one can't wait to see a picture of the first plane toutside this system...
    • "As I am not overly familiar with astronomy, why is this the case?"

      A problem with the phase inducers has knocked long range sensors off-line. Attempting to re-route.
    • From the article: "It currently is impossible to detect Earthlike planets around other stars."

      As I am not overly familiar with astronomy, why is this the case?


      Because Earthlike planets are tiny in the Grand Scheme of Things(tm). We're talking about a "do you see that special grain of sand on that blinding welding torch which is 30 miles away" kind of tiny.
    • Errr... It is not-so-impossible to detect Earth-sized planets in Earth-like orbits about Sun-like stars. There is the "transit method":
      • http://www.rpi.edu/dept/phys/Astro/Ees/Searching _for_Earths.pdf

      Summarizing: if the orbit of an Earth-sized planet is luckily aligned so that the planet occasionally passes in front of its sun in the viewpoint of someone in Earth, then it will dim the light of its sun in 1/10000. That is very little, but detectable with current instruments. And it is the working principl

  • ... because the are also much bigger, meaning that the G force will be much higher. Not that it makes life impossible, but it will create enourmous presures. For life forms on such a planet it would be very difficult to explore space, I guess. Simply, because the escape speed will be very high as well.
    • by Anonymous Coward
      Uh...you do realise that the Earth is a water-rich planet of the type they're talking about, right?
    • Like the Anonymous Coward notes, we live on a water-rich world.

      The press release doesn't give a lot to go on, but it suggests that some of the resulting worlds will indeed be huge, with great deep oceans. But there could be smaller worlds with oceans, big ones without, etc. An interesting mix . . .

      Stefan

  • We have 2/3's of a watery planet right here, that we are yet to explore in great detail.

    • Re:exploration (Score:5, Insightful)

      by NanoGator ( 522640 ) on Wednesday December 17, 2003 @12:48PM (#7746474) Homepage Journal
      "We have 2/3's of a watery planet right here, that we are yet to explore in great detail."

      I hate comments like this. As if astronomers can just take up deep sea diving and marine biology.

      Let's settle this once and for all: Diversification is a GOOD thing. We do not gain anything by 'focusing' on what YOU think is important. I'm a 3d artist. Do you think that somehow qualifies me to do cancer research?

      So knock it off. We do a little bit of everything on this planet. Over-focus on one thing, and you neglect other areas of research that benefit man-kind. You're not being insightful here.
      • My point was simply this:

        Step 1:
        Develop spacecraft with the capacity to traverse, and navigate accurately, distances measured in lightyears.

        Step 2:
        Arrive at the watery planet.

        Step 3:
        It sure would be nice to have some knowledge of biology and deep sea diving so you could SEE WHAT IS ON THE WATERY PLANET.

        If the surface of Mars was covered in water, you can bet that every probe being sent would have some type of submersible payload to cruise around and measure water temp, currents, chemical properties, gat
        • I think you missed his point: While we are doing work on astronomy, it is important to continue to do work on deep sea biology; and, vice-versa. By the time we have developed that spacecraft you speak of, we'll also have the ability to go deep into the watery abyss.

          There's no point in not working on them concurrently -- maybe one area will benefit from discoveries in the other in ways you don't expect...

          • Which has indeed happened. Deep-sea operations have benefitted greatly from the space race, and vice versa, metallurgy, guidance control, communications, etc. :-)
  • by Jesrad ( 716567 ) on Wednesday December 17, 2003 @11:05AM (#7745474) Journal
    Reading the article I can't help but think of all the stellar systems around as archipels of islands spread in a huge ocean. The other islands near ours might be inhabited, too ? That's one more reason to start sending "smoke signals". Or perhaps the current electromagnetic madness we emit permanently might suffice ?
  • by Baron_Yam ( 643147 ) on Wednesday December 17, 2003 @11:48AM (#7745909)

    I'd love to see a series of sims run on a modified Earth model - each sim run with only 1 parameter changed, and then examined to see what would happen to life as we know it, here on Earth.

    For instance, play with the Earth's mass, water content, distance from the Sun, or mass of its satellite. It would be interesting to have an educated guess as to how much each of these values could differ from reality before Earth wouldn't be Earth anymore, and how things would change as we approached those limits.

    • An interesting thought, but, damn, there are a lot of variables. Apart from the ones you named, you could also play with varying the amounts of other important for life elements and chemical (oxygen, carbon, nitrogen, etc.), change the kind of star our sun is, varying the amounts of life-affecting compounds (like methane). It's really mind boggling. I suppose we could just limit the things one could vary in the simulation. It would still be an interesting exercise in trying to determine the upper and lo
      • In terms of elements, I don't think I'd bother playing with oxygen or CO2 levels as they are altered by life - and I think it would be beyond our current modelling skills to change the initial chemical balances and model how life WOULD have developed, given that our ability to model the existing atmosphere pretty much sucks.

        Changing the star type, planet core rotation and composition, etc would be interesting though.

        • Actually, changing O2 or CO2 levels can have an effect. If the change is small, then life will usually work through feedback to repair it. However, the change can also destabilize the delicate balance of the ecosystem, causing it to flip into a completeley different state.
      • SimEarth [mobygames.com] used to do this. It was just a game of course, but the models were quite detailed and realistic as far as they went, and you could learn a lot from it about the way these variables interacted. It even had classic models like Lovelock's Daisyworld [pik-potsdam.de] .
  • by jazman_777 ( 44742 )
    It will be a while before we have telescopes good enough to actually see terrestrial planets and spec out their atmospheric composition, allowing us to reality-check these simulations.

    So, this is not based in reality _quite yet_. There is only one data point!

  • by G4from128k ( 686170 ) on Wednesday December 17, 2003 @11:57AM (#7745993)
    The formation of water worlds would seem to hinge on the relative abundances of H, O, and C as well as the ability of other heavier elements to bind these crucial light elements. The inner system of a forming star seems like a hostile place for hydrogen. Between the hot accreting planets, their low gravitiation pull, and stellar winds, I'd bet that its too easy for a small rocky inner world to lose all its hydrogen and other volatiles.

    Assuming that hydrogen is retained (locked up in the rocks), it then becomes a matter of the C-O balance. If carbon is too prevalent, it will scavenge all the oxygen from the atmosphere and lead to a CO2/hydrocarbon atmosphere (other things, like FE also scavenge oxygen). Only if there is enough oxygen will you get water.

    I wonder how accurately the sim modelled the balance of elements and chemical reaction cycles.
  • Glbsnoop: On this one simulated planet, these "humans" have created a simulator to see how likely earthlike planets are to form! Isn't that rich?

    Qlbthrx: Very amusing, Glb. Now turn off the computer and take out the trash.

    Glbsnoop: Fine. CLICK
  • by exp(pi*sqrt(163)) ( 613870 ) on Wednesday December 17, 2003 @02:16PM (#7747341) Journal
    ...the RPG Traveler [geocities.com] as a kid. I've a hunch that my simulations were as accurate at these.
    • That's where my interest in these things started.

      At some point, I realized that getting into too much detail and realism was a waste of time, if all you needed was an arena for some RPG fun. In fact, it got kind of frustrating to come up with all these fancy, diverse worlds and settings and then have players who only wanted shoot'em'ups and merchant adventures and the like.

      Stefan
  • Adding to the (Score:2, Interesting)

    by Wardish ( 699865 )
    This data just adds to the mystery of where are they. Fermi Paradox [seti-inst.edu]

    By all that's reasonable, if life is common, and this data just increases that likelihood, then it's extremely likely that someone somewhere would have colonized the galaxy.

    Of course there are only a few reasonable conclusions (reasonable as I see it anyway...)

    1. We're the only "intelligent" life around. Meaning that life may be common but intelligence as we see it is such a long shot that we are the only or the first.

    2.
    • Addition:
      5. They ARE here, and have been for a long while but they choose not to make themselves known for whatever reason.

      I'm only half joking...
    • Maybe they all decided that it wasn't worth the trouble to colonize the galaxy and just sent out probes to take pictures. Or maybe they are all locked up inside perfect Dyson spheres that are painted black. Or maybe the government really does have alien ships at Area 51 and {{@#$@

      NO CARRIER

      • Actually I think the Dyson spheres would be black but mostly because that makes the best radiator and trust me, they would be wanting to get rid if waste heat. That or the inside keeps getting hotter until the whole thing glows...

        BTW I always preferred...

        yip...yip...yip...BANG!......NO TERRIER
      • But if (by playing with Drake's Equation) one comes to the conclusion that the galaxy has from thousands to millions of civilizations, then what is the likelyhood of *all* of those civilizations following the same path?

        Even if just *one* of those "countless" civilizations chooses the path of interstellar colonization, then the whole galaxy would be colonized in, say, a few millions years, even assuming "slow" Orion-type spaceships travelling at 0.1c . "A few millions years" is an eyeblink in cosmic time,

    • Re:Adding to the (Score:3, Interesting)

      by Urkki ( 668283 )
      My favourite is intelligence inevitably wiping itself out before they can expand to other star systems. Something like, there's some really nifty way of launching interstellar ships using the stars energy output or tapping energy from parallel universe or something, but actually using it will unexpectedly cause the star go nova, wiping everyone out. Or maybe in 10 years someone discovers a way to make artifical neutron stars, then two of them escape, collide at the center of earth and collapse into a blac
  • by Imperator ( 17614 ) <{slashdot2} {at} {omershenker.net}> on Wednesday December 17, 2003 @03:33PM (#7747978)
    Are any of those worlds "duplicates" of other worlds?
  • Here come the Kevin Costner jokes...

"An idealist is one who, on noticing that a rose smells better than a cabbage, concludes that it will also make better soup." - H.L. Mencken

Working...