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NASA Space Science

Kepler Discovers First Earth-Sized Exoplanets 179

ananyo writes "NASA's Kepler telescope has reached one of its major mission milestones: finding an Earth-sized planet outside the Solar System. What's more, it has done it twice in the same star system. Whizzing around the star Kepler-20, about 290 parsecs (946 light-years) from Earth, is not only an Earth-sized planet, but also something just a touch smaller — a Venus."
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Kepler Discovers First Earth-Sized Exoplanets

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  • by zero.kalvin ( 1231372 ) on Tuesday December 20, 2011 @02:52PM (#38438084)
    Congratulation to NASA. I hope there is a plan for Kepler 2.0!
    • Re: (Score:2, Funny)

      by forkfail ( 228161 )

      There was - but Apple sued, saying that NASA's work infringed on it's patents...

    • by Rob Riggs ( 6418 )
      There was, but Congress won't fund it. Instead, they traded it for a few packages of Depends underwear, a tax cut for their donors, and a massive interest payment.
    • Re:Good news (Score:4, Interesting)

      by Maritz ( 1829006 ) on Tuesday December 20, 2011 @05:52PM (#38440666)
      Sadly the closest thing to this would have been the Terrestrial Planet Finder [] which was a superbly ambitious programme and it's a real shame that it's finally been cancelled after having been mothballed for what seems like ages now. Hopefully Kepler's results with either get the programme going again or provide impetus for a similarly ambitious programme. Ideally we should have a technology that can bring spectrometry to bear on a distant world and give us the chemical composition of its atmosphere. If for example free oxygen were detected that would be incredibly compelling evidence for life as you wouldn't expect to find free oxygen without a process that continually creates it (like photosynthesis).
      • Re:Good news (Score:5, Interesting)

        by Grishnakh ( 216268 ) on Tuesday December 20, 2011 @06:49PM (#38441514)

        What's most pathetic isn't that the US is totally dropping the ball on this stuff, it's that other nations that have the ability to take over this important work aren't bothering to do so. Why aren't the Europeans doing more space exploration? They have 50% more population than we do, many of their economies are stronger (just look at Germany's economy), so what's the problem? All they can manage is one little probe to the outer planets?

        Everyone whines about how America is going down the toilet (which it is), but I don't see anyone else stepping up to fill in, except China (which is much farther behind technologically, so has more ground to cover to catch up).

  • by SJHillman ( 1966756 ) on Tuesday December 20, 2011 @02:53PM (#38438100)
    "but also something just a touch smaller — a Venus." If there's a Venus and no known Mars... then does that mean it's all women? Sign me up!
    • "but also something just a touch smaller — a Venus."

      If there's a Venus and no known Mars... then does that mean it's all women?

      Sign me up!

      Yea, they're sure to be really hot!

      The smaller of the two planets, dubbed Kepler-20 e, is about the size of Venus, with a radius 0.87 times that of Earth. It orbits its star every 6 Earth days and sits at a temperature of 1,040 Kelvin — hot enough to vaporize any atmosphere and leave a solid hunk of silica- and iron-rich rock. Kepler-20 f, the larger planet with a radius 1.03 times that of Earth, has a 20-day orbit. As a result, it is a bit less scorching, at 705 Kelvin. At that temperature, says Fressin, hydrogen and helium wouldn’t survive in the atmosphere, but a shroud of water vapour might.

    • by syousef ( 465911 ) on Tuesday December 20, 2011 @03:57PM (#38438956) Journal

      "but also something just a touch smaller — a Venus."

      If there's a Venus and no known Mars... then does that mean it's all women?

      Sign me up!

      Have you learnt nothing from all your years of watching Star Trek? The women are all blue or green, have 3 breasts, and want to KILL you!

      • I'm not seeing the bad.
      • by mcgrew ( 92797 ) * on Tuesday December 20, 2011 @05:05PM (#38439956) Homepage Journal

        Have you learnt nothing from all your years of watching Star Trek? The women are all blue or green, have 3 breasts, and want to KILL you!

        You know, I was ok with the transporter, and with warp drives going faster than light, but the idea that any outworld species would look anything like us whatever is ludicrous. And most movie and TV sci-fi does it.

        I fight bad sci-fi with more [] bad sci-fi. []

        Oh, and you're confusing Star Trek with Total Recall or HHTGT; I don't remember ever seeing the triple breasted whore of erotica in Star Trek, but she was a Martian in Total Recall, but a Martian decended from humans who had three tits because she was a mutant. Far more believable than a Human-Betazoid hybrid (the subject is covered in the two linked stories).

      • The women are all blue or green, have 3 breasts, and want to KILL you!

        Sounds like my last two girlfriends.

    • by khipu ( 2511498 )

      Death by snoosnoo is overrated.

  • Again (Score:2, Funny)

    by M0j0_j0j0 ( 1250800 )

    Comme on, another planet, it has been a week since the last one, will my extensions work on this one?

  • by vlm ( 69642 )

    Note the previous /. article on the similar topic was about Kepler-22, so I'm thinking this report about Kepler-20 is actually going backwards in time relative to the previous article.

    Once again SIMBAD and have nothing. []

    • by arcctgx ( 607542 )

      Apparently the number 20 was assigned earlier, when the larger outer planets were discovered in this system.

  • by Java Pimp ( 98454 ) <> on Tuesday December 20, 2011 @03:10PM (#38438356) Homepage

    Damn that's fast!

  • by Stoutlimb ( 143245 ) on Tuesday December 20, 2011 @03:13PM (#38438402)

    It could still have habitable temperatures if it was a tidally locked planet. The chances of that occuring increase as a planet approach it's star. Any life on such planets would certainly be interesting.

  • apparent size (Score:5, Interesting)

    by polar red ( 215081 ) on Tuesday December 20, 2011 @03:29PM (#38438608)

    the apparent size of this planet is the same as an object of 0.5 mm on the moon.

  • Seriously, not only did he set the bases of modern astronomy, but he still discovers planets 381 years after his death.
  • Whizzing around the star Kepler-20, about 290 parsecs...

    Just to give you all a sense of scale, the Millineum Falcon would have to be 24 times faster to reach it!

  • Pardon my skepticism, but is the margin of error on this really so small that they can really claim to differentiate between a Venus and an Earth sized planet?

    • You don't mean margin of error I believe, but precision of measurement. And yes, the instruments are that precise.

    • Re:Margin of error? (Score:4, Informative)

      by mbone ( 558574 ) on Tuesday December 20, 2011 @04:27PM (#38439388)

      Yes. These are transit measurements. They see the drop in light of the star, or not. If they see it, they can estimate how much the intensity changes, which gives them the ratio of the area of the star and the area of the planet. They can also time the duration of the transit, which, together with the period between transits and some information about the star, gives them the star's radius, and thus the planet's radius. If you can detect the transit at all, you should be able to get all of these things.

  • "So here's (link at bottom) a surveillance telescope that DARPA is proposing to provide CONTINUOUS (that's what's new) real-time coverage of any spot on earth at a resolution of 3m (the example given was to detect Scud launches). Of course in order to do this, it would need to be in geo-sync orbit which necessitates a whopping big lens, in this case 66 FEET ACROSS!

    So how come I've never heard about this "membrane optics" technology before? (From the picture it appears to be able to make the "lens" extremel

    • by Maritz ( 1829006 ) on Tuesday December 20, 2011 @06:20PM (#38441070)
      Claudio Maccone's proposal to use the Sun as a giant gravitational lens (FOCAL []) is pretty astounding. All you gotta do is send your satellite out to about 550 AU (easy peasy eh?) - I think I recall reading that if you were to train it on a planet in the Alpha Centauri system you'd be able to resolve cars in the street assuming there are cars and streets there (bound to be). Not easy to steer though, you'd need to know well in advance what you were aiming it at. One nice thing is that the focal length goes to infinity, so even if you're shooting further out (say 1000AU +) you're still able to get a great picture.
      • So the obvious thing to do is not to look at some boring distant planet, but look at some star a few thousand light years away. But don't look directly at it, use it as a second gravitational lens to look at *another* star, and indefinitely extend the range of the telescope. Assuming the focal point isn't directly on the opposite side of the gravity well it would be possible to aim the telescope within a small angle and conceivably bend the light path around until it was focusing back on our own planet Ea
  • The Real Question (Score:4, Interesting)

    by PortHaven ( 242123 ) on Tuesday December 20, 2011 @04:12PM (#38439128) Homepage

    Is not will we discover an earth gravity (size is meaningless, it's the gravity that's an issue) planet at earth temperature from it's sun, but when.

    And more importantly, when will we find one with 25 light years from Sol.

    NASA's primary focus right now IMHO should be giving out X-prizes for corporate achievement in space flight and endeavoring to devise means for reaching stars:

    - how to get a probe up to near light speed.
    - how to maintain communication with said probe (most likely via entangled diamonds)
    - get us off this rock (within 150 years)

    • by lennier ( 44736 )

      - how to maintain communication with said probe (most likely via entangled diamonds)

      Entangled diamonds are/aren't a girl's best friend.

    • by jeppen ( 1377103 )
      It would be easier to get that going when we really have confirmed a planet with life on it, so I propose we start with that.

      I'd like to see crowdfunding of research like planet-finding. Let's say 100 million people give $1/month for planet-finding. Every month, the money is distributed according to these rules:
      - All money is distributed within the highest category of planets that has any confirmed planets in it.
      -The money is divided among the 100 smallest (radius) candidates (promoting resolution) wit
      • -The money is divided among the 100 smallest (radius) candidates (promoting resolution) with the smallest candidate getting 100 parts of the money, the next smallest 99 parts, and the last 1 part. (5050 parts in all, the smallest one gets almost $2 million per month).

        Or not.

        The LARGEST one gets almost $2 million per month.

        The smallest only gets $20 thousand per month.

    • It seems a bit early for that, since there's nothing (based in any sort of reality) that we know of capable of doing any of these things. We're going to need a lot more hard science before we have a shot at even thinking seriously about it. Let's stick with the LHC and similar projects and see where that gets us.

    • Re:The Real Question (Score:4, Informative)

      by waives ( 1257650 ) on Tuesday December 20, 2011 @10:26PM (#38443604)
      Stop reading so much science fiction, and try some real science. There will never be FTL communication. ENTANGLEMENT DOES NOT WORK THAT WAY /Morbo
  • when the smallest exo-planet we could see was the size of Uranus.

  • I'm hoping Kepler discovers some Jupiter sized planets, in radius and area, that are really low density, so their gravity is like Earth's - along with the atmosphere. They'd probably lack metals or any heavier elements, though they'd probably better have silicon if their crust is going to look like Earth's surface. If the planet has a moon or an asteroid belt nearby full of those missing elements, space mining might make for a really huge place for humans to spread out on in a familiar style.

    • by suutar ( 1860506 )
      Unfortunately, the only way to get that size and earthlike surface gravity is to have such a low density that there's no solid surface. Saturn is already less dense than water and it still has too much surface gravity. We need rocky planets, and for a rocky planet to have earthlike gravity it's going to have to have a roughly earthlike size.
      • Well, I'm not at all sure we need rocky planets, since we'd be arriving from space and so likely technologically capable of using off-planet rocks for necessary materials, as I said. Also as I said, Earth gravity on a planet with no heavy elements would be proportionally larger in radius and area, though not as big as Jupiter. Since Uranus and Neptune have no cores, they're probably more diffuse and heavier than any planet with Earth gravity and a crust, so the upper bound is somewhere less than them.

        A holl

        • by suutar ( 1860506 )
          A hollow planet solid enough to land/stand/build/live on would indeed be awesome... but it seems improbable that one could form naturally. An artificial one would be even more awesome, but has its own questions (is it available? If so, what happened to whoever built it?)
          • I loved _Ringworld_, too :).

            I wonder what the actually largest (radius) planet would be with Earth gravity but low density (nothing heavier than silicon, and no helium or neon).

  • On behalf of my sovereign nation, the United States of America: I hereby make a territorial claim upon the entire surface of the larger of these two planets, and 75% of the temperate latitudes of the smaller one, wherever they are.

Matter cannot be created or destroyed, nor can it be returned without a receipt.