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New Exoplanet Is Best Yet Candidate For Supporting Life 288

First time accepted submitter uigrad_2000 writes "With all the new exoplanets discovered recently with Kepler, it seemed a sure thing that the first exoplanet in the habitable zone of a star would be found soon. The irony is that Kepler was not involved. GJ 667Cc is at least 4.5 times as massive as Earth, and lies in the habitable region of its host star, reports Scientific American. It was discovered by comparing public data from the ESO to recent observations from Hawaii and Chile. As opposed to the stars Kepler is watching, this is only 22 light-years away, making it even more interesting."
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New Exoplanet Is Best Yet Candidate For Supporting Life

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  • by afabbro ( 33948 ) on Friday February 03, 2012 @01:58AM (#38912169) Homepage

    ETs "finding" us has never been far-fetched. Assume we're not the first sentient species to evolve, most species evolve technologically in a similar way, we're not by some bad luck in an incredibly underpopulated galaxy, etc. These are all reasonable assumptions.

    However, it's the contacting us and/or visiting us that is a lot harder to fetch.

    I'm certainly not an expert, but my understanding is that to listen to our own spacecraft at the edge of our solar system (Voyager) requires a giant dish here. Granted, Voyager is a pretty weak transmitter, but it's also a very close one and one we built and understand. A giant transmitter 22LY away...could the signal reach us? Further away? I don't know. So likewise, what about our signals (which are pretty weak at this point, even when we try) to them? My understanding is that it's more about the signal decay over vast distances than about sophistication in listening equipment. Identifying Earth as a high-likelihood life-sustaining planet by some ETs - sure. Listening in on us or contacting us...much tougher.

    ETs visiting us requires a jump from physics we speculate about to science fiction. At this point, faster than light travel may, for all we know, be forever impossible.

  • by c0lo ( 1497653 ) on Friday February 03, 2012 @02:08AM (#38912215)

    What if we go there? 4.5 G?

    Probably less. TFA quote:

    The discovery of a planet around GJ 667C came as a surprise to the astronomers, because the entire star system has a different chemical makeup than our sun. The system has much lower abundances of heavy elements (elements heavier than hydrogen and helium), such as iron, carbon and silicon.

    Good news: the density/mass of the planet may be less, thus a lower gravitation.
    The bad news: the lack of carbon (which, BTW, is not that heavy) would make the planet unable to sustain life as we know it.

    Other than that, with around 20-something days/year of leave entitlement, living there should be nice, because:

    It takes roughly 28 days to make one orbital lap around its parent star

    "The planet is around one star in a triple-star system," Vogt explained. "The other stars are pretty far away, but they would look pretty nice in the sky."

  • by sgunhouse ( 1050564 ) on Friday February 03, 2012 @03:10AM (#38912445)

    Assuming average density the same as Earth, take a cure root of 4.5 to determine the approximate radius (compared to Earth). Then gravity is M/r^2 which (since we assumed M = r^3) simplifies to r.

    Digging out the calculator, 1.651G.

    (Jupiter is substantially less dense than Earth, that's why it doesn't work for Jupiter.)

  • Re:22 light years (Score:5, Informative)

    by butalearner ( 1235200 ) on Friday February 03, 2012 @09:21AM (#38913829)

    I would not be so worried about Doppler shifted radiation. I would be more worried about the 3 foot tall super strong midgets who would live on a planet with 4.5x our gravity. They would undoubtedly be able to break a human man in half with little effort.

    Actually, the planet's radius is probably going to be quite a bit larger than our own, since (reportedly) there are fewer heavy metals in that system. If the radius is 2.1x Earth's radius with 4.5x the mass, the gravity would be the same as Earth.

  • Re:22 light years (Score:4, Informative)

    by DaleSwanson ( 910098 ) on Friday February 03, 2012 @02:57PM (#38918813)

    I read somewhere (I wish I could find it now) That if you were to accelerate at a constant 1G - The time dilation would allow you to visit the known visible universe within a human lifespan.(Well for the traveler anyway) - I really wish I could remember where this came from, I would really like to know if it was true or just something out of someone's ass.

    Accelerating at 1g allows you to get just about anywhere in about 10-25 years (in your time frame).
    100,000 LY (diameter of Milky Way) 11.8 years
    2.6 million LY (nearest galaxy) 15.0 years
    46.6 billion LY (radius of observable universe) 24.5 years.

    Some important notes: First this would get you to these places travelling at near the speed of light. If you'd like to arrive stopped you'll have to roughly double the travel time, as half would be spent decelerating. Second, you could accelerate as long as you had a source of energy (and a functioning ship).

    As for the claim you could visit the observable universe in a human lifespan, you couldn't reach all the points of it. But you certainly could reach the edge. []

When a fellow says, "It ain't the money but the principle of the thing," it's the money. -- Kim Hubbard