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NASA Space Science

Three Tiny Exoplanets Suggest Solar System Not So Special 83

ananyo writes "Adding to its already long roster of firsts, NASA's Kepler spacecraft has found the three smallest extrasolar planets ever detected — all of them smaller than Earth, and the most diminutive no larger than Mars. The newly discovered trio forms a miniature planetary system orbiting a cool, dim red dwarf star called KOI-961. Because they are so close to their star, the three exoplanets are too hot to support life. But unlike most previously known exoplanets, the vast majority of which are Jupiter-scale gas giants, all three are thought to be rocky worlds like Earth and the other worlds of the inner Solar System."
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Three Tiny Exoplanets Suggest Solar System Not So Special

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  • ... as we know it. Where there is lots of energy there could be something to make use of it.

    • by simcop2387 ( 703011 ) on Thursday January 12, 2012 @02:27PM (#38676282) Homepage Journal

      While that is true, it is nearly impossible for us to determine such things right now. That's why current searches are looking for things that appear to be earth like for the simple reason that we know what to look for. Until we can find other things that we KNOW are life we can hardly begin to speculate on if we are detecting things that might be life but not as we know it. As we get more comfortable in detecting these kinds of things we'll be much much better equipped to come to conclusions for things we haven't seen.

      • by K. S. Kyosuke ( 729550 ) on Thursday January 12, 2012 @03:23PM (#38676958)
        I've read this nice book on how (1) *animal* life (or an equivalent with slightly different chemistry - but still complex and multicellular) might be rarer in the Universe than we previously thought - mainly due to temperature stability problems during the long evolution of said organisms (main sequence stars shining progressively (and significantly) brighter as they age and the ecosphere having somehow to cope with it, which in case of Earth means some kind of CO2 feedback mechanism that tends to stabilize the temperature in a fairly narrow band of temperatures and that might be quite rare in the universe - again, a speculation), whereas (2) an alien equivalent of extremophilic bacteria might actually be much more common than we thought and could make up the greatest potion of Universe's biomass (just as it is on Earth). The question here is whether there are other interesting self-replicating molecules than just DNA and RNA. If not, then I guess we have quite a good idea as to how alien life looks like. (But I love to be proven wrong every now and then...)
        • by mr1911 ( 1942298 ) on Thursday January 12, 2012 @03:43PM (#38677228)

          which in case of Earth means some kind of CO2 feedback mechanism that tends to stabilize the temperature in a fairly narrow band of temperatures and that might be quite rare in the universe - again, a speculation

          The "quite rare" speculation is certainly based on definition. It would be correct to say "quite rare" if even a fraction of a percent of stars have an Earth-like planet. The "quite rare" may not be correct considering that such a small fraction could be billions of planets.

          It is quite amusing that humans want to consider ourselves unique and somehow believe we will be the superior beings when life is discovered elsewhere. I certainly hope not, because it is quite depressing to consider we are the best of what the universe has to offer.

          • The "quite rare" speculation is certainly based on definition.

            The Earth's feature in question was working plate tectonics, with just about the right amount of water on the surface. I can't recall the workings of the feedback mechanism itself, only that it depends on CO2 being released from volcanoes at a rougly constant rate and then being reabsorbed in the crust (and later brought deeper near subduction zones) with the reabsorbtion rate being positively corellated with surface temperature, thus creating a negative feedback loop - or something like that. (Oh, and I've

          • OTOH, most of us have the capacity to recognize the flaws of our species, and we are willing to accept economic inefficiencies in exchange for meeting intangible social and cultural benefits. We really aren't that bad, for the most part.

            Techies tend to have mild BPD, believing most highly in rationality, criticism and determinism, so we're all a bit brain damaged when it comes to sociology and anthropology. I bet a lot of /.ers would think the Vulcans are a better species than humans, for example. They'd pr

          • I suspect that when the best the universe has to offer notices us they will quickly cauterise the wound.
      • by Artraze ( 600366 ) on Thursday January 12, 2012 @03:35PM (#38677110)

        But at that level of pedantry, we might as well assume that life can exist within a star itself, and that planets aren't really important. Or for that matter, maybe these plants are actually large balls of cheese! Until we actually land on extrasolar planets, we can hardly begin to speculate on if what we are detecting are actually rock and gas.

        Astronomy offers only very limited opportunities for observation and basically none for testing. We must supplement what data we can gather heavily using theories and understandings rigorously tested on Earth. While we can't rule out Star Trek style energy beings, for example, we can look at plasmas and their behavior and realize that forming synaptic pathways out is it would basically be impossible. We can draw up some pretty loose limits on life... If it's cold enough that helium is about the only liquid available or so hot that what hasn't melted are only impermeable rigid ceramics, the probability life exists is nil. If it's too hot for a man built machine to function, then it's probably too hot for life as well. It's just a matter of extending what we know about chemical processes, materials and mechanics... Too hot or too cold and making functional and reliable processes, let alone life, is too hard.

        In this case, they are estimating a temperature of 400C. For comparison, silicone and fluoroelastomers top out at about 300C, while highly engineered fluorocarbon oils can only barely get to 400C . Simple hydrocarbons, among other things, can beat that but are highly reactive and can't survive in a reactive environment (particularly with oxygen). Nitrates decompose around that temperature too. So in what medium would life exist? A eutectic salt mixture? But those are so corrosive, what would then contain it? These are the questions the look at and can't answer when they say "life doesn't exist". (And all this doesn't even cover other issues, like the radiation hazards of being closer to the star.)

        If we see a rocky planet at 200C, then we can really discuss how stuck we are on water based life being the only option and how open our minds should be. But this one? It's dead, Jim.

    • by Anonymous Coward

      Exactly what I came here to post (albeit at work, so it's anonymous). I hate it when they use the term "too X to support life", in this case too hot.

      Too hot to support OUR life perhaps, but to say that it's outright incapable of supporting any life whatsoever just makes whoever said that look simple-minded and dead-set on their own theory.

      Sorry, given how insanely, ridiculously massive the universe is, and how many places we've travelled in it, I think it might be be a tad premature to declare that our for

    • That is not necessarily true. Too much energy and the molecules that need to exist, whether carbon based or some other base can't form. Take our own Sun. Plenty of energy there, but if you want self replicating molecules, they can't form long enough to replicate.

      There is a reason we are all sitting on planet earth and not mercury.

  • "Because they are so close to their star, the three exoplanets are too hot to support life."
    Aren't red stars cooler then our yellow sun... Thus the habitable zone will be much closer to the star then for our sun.
    • by itchythebear ( 2198688 ) on Thursday January 12, 2012 @02:14PM (#38676110)

      Yes, that star's habitable zone is probably closer than our Sun's, but the planets are still way to close to be considered in that star's habitable zone.

      FTFA:

      At the AAS meeting, the discovery team announced that all three planets orbiting KOI-961 whip around the star in less than two days. The outermost body is the tiniest, with a diameter half that of Earth, or about the same as Mars, and a temperature of about 400 degrees Celsius. The inner two planets are larger, with diameters about three-fourths that of Earth. But that is still smaller than Venus. Because the planets are all small and close to their star, much of the atmosphere they may once have had would have evaporated, leaving behind bare rock, Marcy says.

    • This is taken into effect whenever calculating the habitable zone around a star.
    • True, but you get too close to anything that big giving up even a fraction of our sun's heat and you're going to have a huge a/c bill. I don't know about these particular planets, but I believe we've found a lot of exoplanets orbiting much closer to their suns than Mercury does to ours.

    • Red stars are cool stars. Since they're red they work at longer wavelengths. Less light is reflected by potential water/ice/snow on the planet surface and kept as heat. Habitable zones of red stars is much larger than other types of stars.

      http://www.technologyreview.com/blog/arxiv/27280/ [technologyreview.com]

  • KOI-961 (Score:5, Funny)

    by Anonymous Coward on Thursday January 12, 2012 @02:14PM (#38676114)

    miniature planetary system orbiting a cool, dim red dwarf star called KOI-961

    Seems fishy ...

  • by G3ckoG33k ( 647276 ) on Thursday January 12, 2012 @02:27PM (#38676294)

    There is a correlation between galaxy arms and possible habitable planets. The idea is not only does the planet have to be the right size, correct distance from the star etc, but also that its location in the galaxy matters!

    Apparently passing through arms of a spiral galaxy is not good for sustaining life. I guess the density of the stars and solar systems must account for that.

    For a starter, http://en.wikipedia.org/wiki/Rare_Earth_hypothesis#The_galactic_habitable_zone [wikipedia.org]

  • So, Kepler is up, in orbit, doing it's thing. Scientists expect to learn a lot, from finally being able to see alien worlds that are a similar size to earth.

    Those of us who are non-scientists know that this isn't really going to be that exciting, unless they find something that differs from are assumptions. We expect that there are many small planets out there, that have not been visible until Kepler. We know that we will never actually "see" these planets. Kepler is just able to watch for periodic chan

    • by youn ( 1516637 )

      What do you mean we'll never see? with the pace at which we've been refining our far space detecting objects, I fully expect that we will be able to see an alien taking a dump galaxies away by the end of the century haha... I say don't underestimate the power of progress... but I have been wrong before

    • by doom ( 14564 )

      Well, here we go with a standard slashdot response ("Ho hum, is this supposed to be news? I did this when I was in high school.").

      Actually, when you've suddenly got a lot of data confirming a commonly held assumption, that actually is news. An article of faith has become scientific fact.

      Wake me up when we get interesting news.

      Nope. It isn't possible. You're going to go through life sleepwalking, copping a faux-jaded pose, deaf to all magic and poetry, oblivious to the music of reality.

  • Almost all of the exoplanets detected seem to be close to their star with short orbital periods. Obviously these two go together. I know enough about these projects to know that there are a variety of methods used to detect exoplanets, but not much more. Are all of these methods biased toward detecting rapidly moving planets more easily, or does it seem that there really are few planets at any greater distances from their primary? Intuitively, it seems that detecting something like Neptune would be hard
    • by thrich81 ( 1357561 ) on Thursday January 12, 2012 @03:55PM (#38677408)
      Kepler detects planets by seeing periodic small drops in the brightness of the host star as the planet passes in front of it. That is only going to work for planets with a pretty short orbital period (I don't know the limit) since they depend on multiple observations to get the orbital characteristics. Neptune with is 100+ year period would not be measurable and unlikely to be observed even once during the mission.
    • by delt0r ( 999393 )
      This uses the transit method where the planet passes between its star and earth, so the orbital plane needs to be edge on. You also need IIRC 3 transits to be a proper observation. Thus to detect earth you need to wait at least 3 years but no more than 4. Jupiter you need to wait up to 48 years! So yes its very biased. I believe this missions max life is 7 years. And yes the planets that are further out will take longer and be announced later.
  • Exoplanets are the new BitCoin? How many "earth-not-uncommon" articles will we have per week?
  • Considering that we live in a galaxy with ~400 billion stars and there billions of other similar galaxies out there, our solar system is not "so special" for sure!
  • by wisebabo ( 638845 ) on Thursday January 12, 2012 @03:50PM (#38677354) Journal

    First Man thought the earth was the center of the (universe) the solar system

    Then he thought the sun was at the center of the (universe) the galaxy

    Then he thought the galaxy was at the center of the universe

    Then he thought planets were rare and that earth sized planets even rarer. Not so! (it looks like)

    Not only is Man no longer at the center of the universe in any figurative sense, metaphorically he is even less so. Solid matter (let alone organic compounds) are a vanishingly small component of what makes up the universe with Dark energy, Dark matter and matter in superheated plasma, black holes or cold interstellar clouds making up the rest.

    All that remains is to (hopefully) find that Life is not rare then Intelligent Life is not rare and that Technological civilizations are not rare.

    But hey, even if so, at least we've got Paris Hilton I mean Kim Kardashian!

    • Intelligent Life, Paris Hilton, and Kim Kardashian. In the same message!

      Ok, i get it. You also referred to "Man no longer at the center", "figurative sense", and "superheated"... Wait, no.

      That beats me.

    • by bertok ( 226922 )

      By definition, you are the geometric centre of the observable universe, which is defined as a sphere centred around you. All other observers are living in the past, and have smaller observable universes that are just subsets of your personal universe. I can talk to you about "my" observable universe, but because of the delay introduced by the speed of light, you can only find out about my observations after some non-zero delay. In that time, your universe would have expanded to include the older, smaller un

  • by no-body ( 127863 ) on Thursday January 12, 2012 @03:51PM (#38677364)

    How many suns exist?
    From: http://www.esa.int/esaSC/SEM75BS1VED_index_0.html [esa.int] :

    "there are something like 10**11 to 10**12 stars in our galaxy"

    From: http://www.universetoday.com/36610/how-many-galaxies-have-we-discovered/ [universetoday.com] :

    "Astronomers think that there are hundreds of billions galaxies in the universe"

    Ok, so estimate 500 billions - thats 500 000 000 = 5 x 10 ** 8

    That would be 5 * 10 ** 19 = 50 000 000 000 000 000 000 possible stars/suns

    That's a number beyond human comprehension and applying any statistical probability will return a true chance.

    So - be assured that "we" are not alone and with current means can never visit other planets within one person's life-span.
    What the heck! In the meantime, the basis for live as it was existing up to now on this planet the human race is going down the tube!

    • by Nemyst ( 1383049 )

      It might be moot (though the interesting thing about exobiology is finding intelligent life forms, not merely life), but mute? It'd be kinda hard to have a discussion this way :)

    • Person's life-span? That's being kind. A Civilizations life-span? Even that is Generous.

      More like species or organism life-span.

      I know calculating going to the last closest exoplanet they announced at Voyager speeds (it being the only thing we have flung out of our solar system for comparison) would take approximately 14 Million years travel time. And that estimate is if you smash into the planet not bothering to try and decelerate! :)

    • that's an assertion without any proof, there are a few peculiar things about our Earth and the Sol system that might not have happened anywhere else. Really.

      • by no-body ( 127863 )

        Total baloney! You have no clue about probability and chance - just stay proud about your perceived uniqueness and be happy.

        • The really big sticking point for me is the formation of fossil fuel deposits on Earth - so many things in both biochemical and geological evolution had to go just right that it might be exceedingly rare, and necessary for bootstrapping things like solar- and nuclear-derived energy.

          So while lots of planets may harbor life, and some tiny percentage but substantial number may harbor bronze age-level civilizations, I think it's possible that we could be the only place in the Milky Way with a technological civi

          • by dkf ( 304284 )

            The really big sticking point for me is the formation of fossil fuel deposits on Earth - so many things in both biochemical and geological evolution had to go just right that it might be exceedingly rare, and necessary for bootstrapping things like solar- and nuclear-derived energy.

            Well, we don't know the probability of such deposits forming given that life is present. We have absolutely no idea whether it is likely or not, as we only know of one place with life and only have had the ability to properly look elsewhere for a very short time. The jury isn't out; the jury's not yet been sworn in.

            So while lots of planets may harbor life, and some tiny percentage but substantial number may harbor bronze age-level civilizations, I think it's possible that we could be the only place in the Milky Way with a technological civilization. Sad, but how do you account for Fermi's Paradox?

            Too many possibilities to say. To be fair, our current technology would be hard-pressed to look for Earth from a distance equivalent to Proxima Centauri, so it's not surprising that we've not see

          • by no-body ( 127863 )

            Once I saw a demo by a forest person about some geological features. He had a 2 m stick and said this represents the age of the earth (making comments about subsections). Then he asked what the age of humanity would be on that scale and to give the answer, he put a sheet of paper on top of the stick. The thickness of this paper represents the time humans are on this planet.

            To put this (and you) on a cosmic scale and time with galaxies, universes and super clusters of universes wanting to make any guesstima

  • WTF else would they be, gas midgets?!

  • Find me a solar system with 8 planets and then claim that ours is not special.

  • I think we're getting to the point where "Kepler detects planet" is just not newsworthy anymore. Even if it's a small planet.

I tell them to turn to the study of mathematics, for it is only there that they might escape the lusts of the flesh. -- Thomas Mann, "The Magic Mountain"

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