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Our Solar System: Rare Species In Cosmic Zoo 197

astroengine writes "Pulling from 20 years of research since the first discoveries of planets beyond our solar system, scientists have concluded that Earth and its sibling worlds comprise what appears to be a relatively rare breed in a diverse cosmic zoo that includes a huge variety of planet sizes, orbits and parent stars. The most common systems contain one or more planets one to three times bigger than Earth, all orbiting much closer to their parent stars than Earth circles the sun, says astronomer Andrew Howard, with the University of Hawaii."
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Our Solar System: Rare Species In Cosmic Zoo

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  • by Anonymous Coward on Friday May 03, 2013 @12:33AM (#43617425)

    That's because the current methods used to detect exoplanets are biased towards large close in planets. As technology progresses we will get more diversity.

  • by Anonymous Coward on Friday May 03, 2013 @12:35AM (#43617433)

    We're still really bad at detecting planets that are NOT bigger than Earth and orbiting much closer to their parent stars? Seriously, whether we use light occlusion or observing the star's wobble, this is the only type of planet we know how to detect.

    Turns out if you're color blind, red and green are very rare and special colours.

  • Re:God made it. (Score:3, Insightful)

    by bejiitas_wrath ( 825021 ) <> on Friday May 03, 2013 @12:36AM (#43617435) Homepage Journal

    The Universe is so large that it cannot possibly be that we are the only life thriving on a planet orbiting a star. There would be countless other lifeforms out in space on countless planets. I wonder if it is possible that a rogue planet could harbour life. Say if it was thrown out of a solar system but volcanism was keeping it warm enough for life to survive. How long would that last? As that was a plot point in Star Trek Enterprise.

  • Re:God made it. (Score:5, Insightful)

    by Black Parrot ( 19622 ) on Friday May 03, 2013 @12:40AM (#43617451)

    See? We are the only place in the universe that can sustain life.

    Great. Now that we've got that established, we can argue over which god made it.

  • by ( 1140205 ) on Friday May 03, 2013 @12:52AM (#43617485)
    Using any of the techniques of observation of extra-solar planets it needs 3 orbital periods to confirm a planets existence, with Kepler observatory this means only planets with a period of 1y can be confirmed. Jupiter has a period of 11.9years, so observations of nearly 36 years are needed for this planet and Neptune is 164years, thus requiring observations over nearly 500years, and then for the outer dwarf planets the observation time needs to be over 1.5 millennia. So, obseratvion of 20 years means the search has only started and not that this solar system is weird.
  • by kenwd0elq ( 985465 ) <> on Friday May 03, 2013 @02:09AM (#43617721)

    The problem isn't that there are no planets in more distant orbits; it's that the Kepler Space Telescope is designed to detect occultations, when a planet passes between the star and us. I am frankly ASTONISHED that Kepler has discovered SO MANY planets in so close to the parent star, but a civilization in the Tau Ceti or even Alpha Centauri system would never be able to detect the Earth - because none of our planets ever occult the Sun from their viewpoint.

    Look up in the night sky, and imagine those distant (and very hypothetical!) civilizations orbiting those many, many stars and trying to find US.. Using a Kepler-type telescope, ONLY civilizations that are pretty darn close to the ecliptic would be able to detect OUR solar system.

    For Kepler to have discovered so many planets, there must be planetary systems around virtually every star out there. There may be a trillion stars in the Milky Way. If only one in a million planets host anything even remotely resembling "life", there must be a million planets with some form of life.

  • by symbolset ( 646467 ) * on Friday May 03, 2013 @03:44AM (#43617987) Journal
    What AC said. Almost all stars have at least one, usually two or three, rocky bodies in the habitable zone. Sometimes they are moons, sometimes planets. But they are almost always there. The exceptions are obvious: stars with stars in that zone (tight binaries), exploded stars, stars that are too young to come steady, Population III stars poor in metals and so on. When we can see them, we will find them. Until then, studies like this that survey observations that could not see such a thing are just a waste of time.
  • Re:God made it. (Score:5, Insightful)

    by StripedCow ( 776465 ) on Friday May 03, 2013 @06:36AM (#43618467)

    The Universe is so large that it cannot possibly be that we are the only life thriving on a planet orbiting a star.

    There is a huge fallacy here.

    The reason that we are on this planet is of course the fact that life IS possible here. However, the chances of life occurring somewhere might be 1 in a gazillion.

    It might even be that life exists only in a small part of the multiverse ( Let us assume that at the sub-atomic scale, decisions are not taken at random, but that at every (let's say binary) decision the universe splits in two halves (one half taking one outcome of the decision and the other half the other). Then if --in this big tree of universes-- life exists somewhere, then it may appear in one universe as if either there was a God that created this life, or, to the more scientifically oriented life-forms, it may seem that life may occur elsewhere in the same universe. But the reality is that the formation of life may be much less likely than we think, and other life may exist only in parallel universes.

    Yes, we have created small DNA-like structures in reaction chambers. However, life on Earth will not function with only some random string of DNA. Complicated machinery (ribosomes etc) is needed to actually make life work. And we know absolutely nothing about the probability of this machinery to come into existence from scratch.

  • Re:God made it. (Score:5, Insightful)

    by hairyfeet ( 841228 ) <bassbeast1968@gm[ ].com ['ail' in gap]> on Friday May 03, 2013 @08:03AM (#43618819) Journal

    Which was why Roddenberry did it that way, I saw an interview with him once where he was asked why all his aliens were forehead aliens instead of anything exotic and he pointed out 1.-The exotic aliens on Dr Who looked like crap, and 2.-90% of an actor's craft is done with his face and when you can no longer see the actor's face he can no longer convey emotion. Joss Whedon said the same thing when asked why he got rid of the cool "American Werewolf" in the first season for a classic wolfman, he said all the animated wolf could do was snarl, it couldn't be scared or show pain or any emotions whereas Seth Green could make you feel for the monster by putting bits of the man into the performance.

    As for TFA, to quote Ian Malcolm "Life finds a way". Just look at how there is life on this planet in some of the most hellish places, like thermal vents on the bottom of the ocean. I remember reading an article talking to the guys that went down so deep in the Marianas trench and one of the things they were talking about was how you had flat fish even down that deep. To say that our planet is so far unique for supporting our monkey asses is fine and dandy but anybody who thinks that means there couldn't be life on those because we wouldn't survive is just being arrogant. This is why i support exploring the oceans of Europa with a probe, from what we saw the oceans under the ice are warm and flowing, if there is any place in our own solar system that would have life my money would be on Europa.

    The problem isn't that there may or may not be life out there, the problem is even in our own galaxy the space is just so damned vast that just saying hello could take 10 million years. Until we can find a way around that pesky little relativity thing we are just pulling ideas out of our asses because with our best telescopes its the equivalent of stepping out a single inch, our reach is just too small when compared to just what is in our own galaxy, much less the thousands of other galaxies, that for all we know earth like planets are a dime a dozen, there just aren't any in the few feeble inches we can reach out with our current tech.

  • by smpoole7 ( 1467717 ) on Friday May 03, 2013 @08:44AM (#43619029) Homepage

    > Rare Earth

    I assume you're speaking of the book by Peter Ward and Donald Brownlee? I'll have to look at that one. As I've posted here previously in other threads, I recently finished Alone In The Universe by John Gribbin, which reaches the same conclusion. I don't know about Rare Earth, but Gribbin's book is based on tons of new computer simulations.

    Gribbin points out that *simple* single-celled life may indeed be common within the Galactical Habitable Zone. That's an extremely important distinction. Making intelligent life is the trick. A number of very unlikely things have to work out for that.

    This flies in the face of intuition. (And besides, Geeks have gotten so used to seeing Klingons and Drazi and Wookies in movies and on TV, it's just taken for granted now.) We just *assume* that the natural end course of evolution is some form of intelligence: give evolution a good, robust single cell to work with and a few billion years of time, and you will inevitably end up with some form of intelligence. But that's not necessarily so.

    As someone else points out here, those who actually study this stuff are reaching a consensus that intelligent life (again, don't miss that!) may indeed be extremely rare in our universe. Yes, even though the universe is huge and large and unfathomable.

  • Re:Call me silly (Score:3, Insightful)

    by amaurea ( 2900163 ) on Friday May 03, 2013 @09:42AM (#43619399) Homepage

    You and a whole horde of other slashdotters have had the idea of ease-of-measurement bias - a large fraction of the posts on this article mention it. Thankfully, the researchers who study these planets have also thought of it. They have even measured how large it is, and corrected for it. One result of this is that even though we see a large number of hot jupiters, we know know that planets get more common the smaller they are. That is actually one of the main points of the article. I guess this goes to show how many actually read it.

  • Observation (Score:4, Insightful)

    by DarthVain ( 724186 ) on Friday May 03, 2013 @01:20PM (#43621931)

    Well until we actually observe other alien life the scientific assumption should be that most life is like ours, that ours is the path of least resistance, the optimal path that all life takes. I think we should be open to it being radically different, however until we observe anything to the contrary, it is all just so much speculation. It could be that some life is so radically different that we may have a hard time recognizing to even observe it. It could be that we are the life oddballs, and most take another path. Who knows. However at this time the most rational response would be to surmise that at least at this time, life is likely similar to ourselves.

Someone is unenthusiastic about your work.