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Looking For Earth-Like Exoplanets

Posted by Soulskill on from the dust-motes-orbiting-a-yottawatt-light-bulb dept.

Discover Magazine is running a story detailing the search for planets like Earth orbiting other stars. While we've been able to locate a few "super earths" so far, none of them really compare in size or the potential for habitability with our own world. Fortunately, advances in data analysis and new space-based telescopes — such as Kepler, the James Webb Space Telescope, and the already-launched CoRoT (PDF) — have some astronomers predicting we'll find such an exoplanet by 2010, and a habitable one by 2012. Earth-based telescopes are also in the hunt, though the article notes, "even if a habitable Earth-like world is found first from the ground, it will most likely take a space observatory to search for the chemical signals that tell us what we really want to know: Is anything living out there? If the planet is one that can be observed transiting, it just might be possible to provide a hint of an answer in the next few years."

7 of 73 comments (clear)

  1. Wow... An article about planets that isn't... by Devout_IPUite · · Score: 4, Insightful

    Obsessed with the fact we haven't observed something we can't yet detect... This must be some sort of mis-post.

    1. Re:Wow... An article about planets that isn't... by John+Hasler · · Score: 3, Funny

      Why such a low upper limit on gravity? Lichen don't care what they weigh.

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      Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
    2. Re:Wow... An article about planets that isn't... by arminw · · Score: 3, Interesting

      ... I wonder what the parameters for "earth like" should be....

      Do you mean by that the conditions necessary to develop intelligent life, such as the SETI project is looking for? Assuming that the laws of physics are the same everywhere in the universe, the molecular binding energies for living things would dictate the temperature range. For practical purposes this would mean the temperature range in which water remains liquid at least some of the time. This would require a stable orbit around a star the output of which does not fluctuate too much. Orbital mechanics show that such a star must not have a neighbor closer than about 3.8 ly. By that specification alone, about one half of all stars in the universe are disqualified from having such a planet because they are too close to each other.

      Really big stars are also disqualified because their output varies too much in order for intelligent life to develop or exist. If a star is too small, a potential planet must be placed too close in order to get enough heat. Any such close in planets all are unlikely to freely rotate, thereby having one side always facing the star. That would mean the dark side would get extremely cold. Assuming there was a viable atmosphere, it would circulate violently between the day and night side.

      Living processes involve large complex molecular structures which only the element carbon allows. Therefore, any physical life must be based on the chemistry involving carbon. Of course, there may be nonphysical life, but that is not what we are talking about here.

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      All theory is gray
  2. Super Earths??? by owlnation · · Score: 3, Funny

    ...we've discovered the planet Krypton?

  3. The future is 2012 by MR.Mic · · Score: 3, Funny

    From what I understand from all the latest the tech news on /., we are going to have a super-awesome sci-fi future world in 2012.

  4. Re:But... by name*censored* · · Score: 3, Funny

    Increase the rotational speed of the planet so much that the centripetal force counteracts gravity. Then, with giant nets, catch the oil as it floats up from the surface. Then, pump it through a hose and squirt it back to a giant funnel sitting outside earth. I mean, our only other alternative is NON-fossil based fuels, and that's just CRAZY!

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    Commodore64_love: I don't comprehend people who're so frightened of death that they'll bankrupt themselves to stay alive
  5. Re:High resolution images possible in near future? by ceoyoyo · · Score: 4, Interesting

    It's harder than that. I assume by "see" you mean two-dimensional visible or near-visible light images. To produce images like that you have to be able to move each telescope in your interferometer (or have lots of them), in two dimensions. The big radio interferometers put the radio telescopes on train tracks. Some proposals for space interferometers put one on each end of a tether, spin them, then winch them closer and farther apart to trace out a spiral.

    The other problem with crazy long baseline interferometry is that you need to transmit the received signal (including phase) between the individual elements. For radio that's not too bad because you can actually detect and record the phase, for low enough frequencies. For optical it's much harder.

    Plus you have the problem that interferometers have great resolution but poor light gathering capability. They can't see things that aren't bright.

    A back of the envelope calculation (which might be wrong) shows that a 50 km city at 50 light years would be about 2 x 10^-5 miliarcseconds. To get that kind of resolving power in the middle of the visible spectrum you'd need a telescope about 6000 kilometres across. That's not too insane. You might be able to pull it off with an array of a hundred or so reasonably sized space telescopes all orbiting around a L point somewhere. If you could collect enough light, and distinguish between the city light, the non-city planetary light and the star, of course.