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Earth-Like Planet That Could Sustain Life Found

Posted by samzenpus on from the guess-who's-coming-to-dinner dept.

astroengine writes "An exoplanet, 20 to 50 percent the mass of Earth, has been discovered 20 light-years away and it appears to have all the ingredients conducive to sustaining life. It has enough gravitational clout to hold onto an atmosphere and it orbits well within the 'Goldilocks Zone' of its parent star. However, it would be a very different place to Earth; it is tidally locked to its star, creating one perpetual day on the world. Interestingly, this may also boost the life-giving qualities of the exoplanet, creating stable temperatures in its atmosphere."

9 of 575 comments (clear)

  1. Only 20 light years??? by brunes69 · · Score: 4, Interesting

    20 light years is millimeters of astrophysical distance.

    It amazes me we have been observing space so long and yet we only now have detected this planet.

    It just goes to show how incredibly likely it is to find planets like Earth everywhere in the galaxy.

    1. Re:Only 20 light years??? by huckamania · · Score: 3, Interesting

      The only way for humans to get to another star is to learn how to live in space. It is not so daunting a task as most believe. The most important fact is that space is not empty. There are more resources in the asteroid belt then currently exist on Earth and the vast distances between the stars are filled with resources that dwarf the already immense asteroid belt.

      It is all out there waiting for us. With the current rate of innovation, I would expect that we are only a few generations away from taking our first real steps into conquering our solar system. After that, it will be only a few more generations until we start spreading out into the beyond. We are really only missing a few key ingredients to take those first steps, most importantly we lack the political/social will to explore space.

      It will not be cheap to move into space, but the upside is supercalifragalistic (seriously, couldn't think of a better word). It will mark the beginning of our post-scarcity existence.

      If we don't move into space, we will continue to mark time until the end of our existence.

  2. Humans are so fragile...if only we were hardier by mykos · · Score: 3, Interesting

    Ethics aside, wouldn't it be easier to genetically modify humans to live in a wider variety of environments? Seems like it would be a far more reachable goal in the near term than getting to these distant planets.

  3. Time dilation woes. by Anonymous Coward · · Score: 5, Interesting

    My math might be a little off, but if we accelerated at g half-way there and decelerated at g for the rest of the way, it would only take a ship about 6.04 years to get there. But thanks to Einstein ruining all our space travel fun with relativity, we of us left on Earth would think the journey took 21.86 years. So there and back would seem like 43.7 years to us.

  4. I work with 2 of the authors by Theory+of+Everything · · Score: 5, Interesting

    I actually work quite closely with 2 of the authors of the paper that reports these results. Any questions? I'll try to respond to posts between now and 2 October.

    1. Re:I work with 2 of the authors by Theory+of+Everything · · Score: 3, Interesting

      Honestly, that conclusion was a bit premature. The other coauthors (including my coworkers) avoided speculating on this point.

      His conclusion was based on the idea that where liquid water can be present, so far we have always found life to within out ability to identify it. Thus, since there seems some high probability that liquid water *could* exist on this planet (though no evidence thereof, yet---it just seems likely due to the temperature and because water is such a simple and universally common molecule), and where we've found water we've found life (even in circumstances that would be considered unpleasant), he jumped to saying life was likely.

      I personally think that it is premature to speculate on life in this system, since so little evidence is available. If pushed to make a call by Vegas, I'd have to say life was more likely than not on this planet, but my line would not be near 100%. Probably closer to 60/40.

    2. Re:I work with 2 of the authors by w0mprat · · Score: 3, Interesting

      Aren't Red Dwarf stars often unstable and known as flare stars? This would be a problem for life in the Gliese system? Or is Gliese more stable being larger than most of these?

      Is there any meaningful insight into the balance of elements in the stellar system (from looking at the spectra of the star) that would help guess the composition of the rocky planets - would there be plenty of the right stuff for life? I ask because I read Gliese is 7-11 billion years old and older stars have less heavy elements, I'd guess that the system would not have the same abundance of metals and heavier elements.

      Does the spectra of a star give any clues to the abundance of water in the star system? At least upper and lower bounds?

      --
      After logging in slashdot still does not take you back to the page you were on. It's been that way for 20 years.
  5. Re:And the odds of habitable aren't that great by tomhudson · · Score: 4, Interesting
    There's no free water - it's all a sulfuric acid haze. Spin-locked planets don't have enough tidal stress to drive plate tectonics, so there's no recycling of CO2 - all the CO2 that's in limestone, etc., that gets subducted? It gets baked out into the atmosphere instead. You end up with YAV - Yet Another Venus.

    We're here not just because we're in the Goldilocks zone, but also because we're a double-planet (earth and moon). Lots of gravitational stress to help encourage crustal slip along fault lines, and free water to help with the slippage. A runaway greenhouse effect caused by much higher CO2 concentrations converts the water to H2SO4. Once the water is gone (it's still liquid at depth even at 150C because of the pressure), the plates lock up completely, and you get Venus.

  6. Re:Annddd.... by rahvin112 · · Score: 4, Interesting

    There is an argument to be made that because of the very physics of the universe that life itself may be not only inevitable but practically guaranteed. This statement is made with consideration of organic chemistry and the pervasiveness with which hydrocarbons not only exist but seem to interact and react to other hydrocarbons. Carl Sagan was the biggest proponent of this hypothesis, that the physical laws of the universe predispose the creation of life. If the hypothesis is correct, that hydrocarbons are so common throughout the universe (which they are) and that their interaction to form amino acids and the basis of life itself is the end result of the laws of the universe (supposition at best) then if a planet is the right temperature, has water and carbon then life should form. (note mars isn't warm enough and has no free water and Venus is way way to warm, but Titan is literally covered in lakes of liquid hydrocarbons)

    I agree the guy is a bad scientist for making such a claim, but if you believe this line of reasoning then if you can find a star with planets in the habitable zone, the right size, with water and enough carbon then you will have life "guaranteed". They are just on the cusp of having enough technology to see earth size planets, I think it will be just a mater of time till they can spectrograph the light bouncing off the planet and can find out which ones have oxygen in the atmosphere. Once you find oxygen you know you have life, at least minimal enough life to create free oxygen which can't exist without life because of it's highly reactive nature. I believe Carl was right, that life is an inevitable consequence of the universe, but until we have a better understanding of exosolar planets and that our solar system(and the earth itself with it's super-sized moon and high rotation) isn't unique we don't have the ability to say life is guaranteed anywhere and that's what makes his assertion so silly even if he believes Carl's hypothesis.

    It's an interesting area, because you could test the theory. With some massive expenditures of cash it would be possible to stop the run away greenhouse effect on Venus. Once the planet cooled it would rapidly lose much of it's excess atmosphere and attain a condition not that much different than the early earth except for the very slow rotation and lack of a moon. That test would then prove whether the moon (tidal forces) and fast rotation (short nights) were special or essential in the creation of life. If those two variances are important than life could still be quite rare even with the universal predisposition to life from the right physical circumstances. It's been argued that life first started in the tidal pools on earth, without tides you don't get the periodic flooding that life in the current tidal pools needs to survive. Whether life can survive nights that last multiple days or even weeks is another argument that has little to no evidence to support.

    Anyway, I don't agree with the scientists affirmation but I do understand why he would believe so strongly that life is guaranteed if the conditions are right.