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Solar Systems Like Ours Are Likely To Be Rare

Posted by CmdrTaco on from the i-prefer-my-solar-system-medium-rare dept.

KentuckyFC writes "Astronomers have discovered some 250 planetary systems beyond our own, many of them with curious properties. In particular, our theories of planet formation are challenged by 'hot Jupiters,' gas giants that orbit close to their parent stars. Current thinking is that gas giants can only form far away from stars because gas and dust simply gets blown away from the inner regions. Now astronomers have used computer simulations of the way planetary systems form to understand what is going on (abstract). It looks as if gas giants often form a long way from stars and then migrate inwards. That has implications for us: a migrating gas giant sweeps away all in its path, including rocky planets in the habitable zone. And that means that solar systems like ours are likely to be rare."

13 of 394 comments (clear)

  1. Well, that does it... by BigDaddyOttawa · · Score: 5, Funny

    Get Bruce Willis on the phone, time to go "Armageddon" on Jupiter's ass.

    --
    Sig? SIG? We don't need no stinkin' sig!!!
    1. Re:Well, that does it... by Anonymous Coward · · Score: 5, Funny

      On the other hand, the rest of us wish you'd learn to spell "probability".

    2. Re:Well, that does it... by Sebilrazen · · Score: 5, Informative

      Haha. I don't know about sending Bruce WIllis, but this does make me wonder why we have never (to my knowledge...) sent a probe INTO one of the gas giants.

      Your geek credits have been officially revoked.

      Galileo had a probe that was dropped into the atmosphere of Jupiter and it transmitted data for 58 minutes before it stopped. Hell, we even crashed the Galileo spacecraft into Jupiter to prevent contaminating Europa or Callisto with organisms from Earth.

      --
      "There are no facts, only interpretations." --Friedrich Nietzsche.
    3. Re:Well, that does it... by MrKaos · · Score: 5, Funny

      On the other hand, the rest of us wish you'd learn to spell "probability".

      Maybe he should use a spell chequer!!

      --
      My ism, it's full of beliefs.
    4. Re:Well, that does it... by RogerWilco · · Score: 5, Informative

      We have.

      in 1995 by the Galileo a probe was dropped into Jupiter.

      http://apod.nasa.gov/apod/ap951207.html

      But if you think it will just sink in until it 'hits' then check your physics on large gas giants again.

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      RogerWilco the Adventurous Janitor
    5. Re:Well, that does it... by Captain+Hook · · Score: 5, Informative

      Whatever... this is naval gazing and conjecture, no more credible than Intelligent Design. These guys have a few data points, they create a highly convoluted system that seems to account for their data points, then the moment they get more data, they start over. Again and again.

      Data points which are skewed by the fact that planets with a large mass (relative to the star) orbiting close to the star are easier to detect by techniques based on star wobble and transit light level and so are going to be massively over represented in the list of known planetary systems.

      --
      These comments are my personal opinions and do not necessarily reflect the opinions of the other voices in my head.
  2. Rare? by east+coast · · Score: 5, Insightful

    I didn't RTFA, but I will when I get home.

    But on the surface it seems more to me that they're just saying that solar systems have a life cycle that is marked by the location of gas giants. I don't really think that means that our setup is rare.

    But if I am misinterpreting the blurb and that is what they're proposing I would still say we need to hold our horses on any real judgement. We've found these solar systems because our current method of seeking these solar systems out is going to be more likely to find this kind of activity as opposed to what we have here at home. I think we're jumping the gun a bit on this one. I say let them work it out for a couple of more decades and even then we should be a bit more cautious about such sweeping statements.

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    Dedicated Cthulhu Cultist since 4523 BC.
    1. Re:Rare? by mapsjanhere · · Score: 5, Informative

      The method used to find these systems are changes in the star's brightness when the planet passes in front of the star - so systems with large planets in close orbit are the ones to be noticed first. If you have a planet like Jupiter with an orbital period of around 12 years, you're much less likely to catch that event compared to those "unexpected" systems with short periods.

      --
      I'm aging rapidly, I bought a new game and had no idea if my machine was good for it.
    2. Re:Rare? by shma · · Score: 5, Insightful

      The parent is correct that there is a selection bias in our detection methods of planets that favours systems with gas giants close to the sun. However, this has nothing to do with the conclusions of the article. What they are saying is that, initially, the discovery of so many closely orbiting gas giants was confusing given that their models of planet formation show gas giants developing far away from the sun. What they have found through simulations is that gas giants naturally migrate inwards as the solar system evolves. So a 4 billion year old system like ours with gas giants far from the sun in unlikely. This conclusion comes from the simulations of solar system evolution, not from the observational data.

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      I came here for a good argument
    3. Re:Rare? by Hektor_Troy · · Score: 5, Interesting

      That's still rare. If we assume that there's 100 billion galaxies in the world (which Wiki says is the current estimate), and put a star system like ours on the rare end of the scale as in 1 per galaxy, you do end up with 100 billion star systems like ours. But that's still extremely rare, as it's pretty much impossible to find one.

      Look at it another way: In 2006 the world supply of platinium was about 217,000 kg. That's about 1,112,341 mole or 667,404,810,235,590,822,414,959,709,663 molecules. That's a BIG number, but it's still a very rare metal. So rare in fact, that 2006 world supply wouldn't even let you give 1 gram of platinum to each resident of the United States.

      Big numbers doesn't indicate how rare something is. Rare is an indication of the chance/risk of encountering something. And in a huge universe with 100 billion galaxies, 100 billion star systems like ours is RARE! In fact it's so rare, that it might as well not exist anywhere else, because without visiting other galaxies, we'd never know they were there.

      --
      We do not live in the 21st century. We live in the 20 second century.
  3. This appears to be a "When you are a hammer ..." by SengirV · · Score: 5, Interesting

    "... Everything looks like a nail" situation to me. We've only really had the ability to discover LARGE planets around solar systems. Also, the shorter the orbit period, the easier it is to detect.

    So logically, the planets we've found to date look NOTHING like those of our solar system. Jupiter's orbital period is 4332.71 days!!! And we are comparing that to the VAST majority of discovered planets(hot Jupiters) with orbital periods of less than 10 days?

    Seems like this article belongs in the "Are US Voters Informed Enough About Science?" thread if you ask me.

    --

    Prof. Farnsworth - "Oh a lesson in not changing history from Mr I'm-My-Own-Grandpa!"

  4. Re:first post by The+End+Of+Days · · Score: 5, Funny

    Nothing says "sanity" like a preemptive defense.

  5. Re:first post by colmore · · Score: 5, Informative

    Outsider theories always have the burden of proof on their own shoulders. To paraphrase someone famous, "there are many questions fools can ask that wise men struggle to answer." There's no where this applies more than in science. Creation Science can throw out some sticky questions and make some points that are hard to disprove.

    But Science is about proving things, not suggesting every possible idea and disproving them one by one. For a well established idea that has made a lot of successful predictions, even a known incomplete idea like the standard cosmological model, to be tossed aside, there needs to be an overwhelming amount of evidence, not just some compelling questions.

    If an alternative model of the universe explains the preponderance of evidence we already have (such as the background radiation, the count of galaxies, the scarcity of structures above a certain scale, the calculated mass of galaxies, the total amount of gamma radiation etc.) as well as a current theory, as well as making successful new predictions that existing models failed to make, then over a process of several years, people in the field would become convinced, and as the literature is peer reviewed, the dogma would shift. But established scientific ideas are SUPPOSED to be dogma. It isn't politics. Equal time isn't given to competing ideas, that's not the way it works. There are too many bad scientists and professional crackpots, the system would collapse without a hierarchy of opinion.

    And all science works this way and always has. Even the sciences that cure disease and deliver technological miracles. Since those things keep happening, I'm confident as a semi lay person that science, while certainly getting many small details wrong and making mistakes and sometimes taking too long to come to the right conclusions, is still heading in a monotonically positive direction.

    --
    In Capitalist America, bank robs you!