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Newfound Planet Has Earth-Like Orbit

Posted by Zonk on from the hooray-for-earth dept.

Raver32 writes with a link to the Space.com site, and an article discussing an extra-solar planet that looks a lot like ours from a distance. At least, its orbit does. The planet is located about 300 light years away, in the constellation Perseus. It circles its giant red star every 360 days and was discovered by 'looking for wobble', the shift in a star's movement that hints at orbiting planets. "The discovery could help astronomers understand what will happen to our sun's brood of planets when it exhausts its store of hydrogen fuel and its outer envelope begins to swell. When that happens in an estimated 5 billion years, our sun will be so big that it will engulf the inner planets and most likely Earth. But long before that happens, life on our planet will have perished and its seas will have boiled away."

11 of 126 comments (clear)

  1. Change in Orbit by Anonymous Coward · · Score: 1, Informative

    Actually, I have read that the earth may be pushed out to a farther orbit, so we wouldn't get 'swallowed' by an expanding sun.

    1. Re:Change in Orbit by pauljlucas · · Score: 4, Informative

      Actually, I have read that the earth may be pushed out to a farther orbit, so we wouldn't get 'swallowed' by an expanding sun.
      Right, because the sun will blow off mass into space. A less-massive sun will have weaker gravity so everything in orbit will move farther out.

      But it probably won't matter much because the sun as a red giant will be far hotter and far more luminous so the orbital distance increase won't be enough to compensate.

      --
      If you reply, do so only to what I explicitly wrote. If I didn't write it, don't assume or infer it.
    2. Re:Change in Orbit by meringuoid · · Score: 3, Informative
      But it probably won't matter much because the sun as a red giant will be far hotter and far more luminous so the orbital distance increase won't be enough to compensate.

      It will be far more luminous, but substantially cooler: around 3000K rather than the current 5800K. It'll still cook the Earth without difficulty, though.

      --
      Real Daleks don't climb stairs - they level the building.
  2. Life will be there after the oceans boil away by InterGuru · · Score: 4, Informative

    A Princeton-led research group has discovered an isolated community of bacteria nearly two miles underground that derives all of its energy from the decay of radioactive rocks rather than from sunlight.

    Subterrainian Microbes

    This type of bacterium, approximately four micrometers in length, has survived for millions of years on chemical food sources that derive from the radioactive decay of minerals in the surrounding rock, making it one of the few creatures known that does not depend on sunlight for nourishment.

    These will survive any surface conditions, until the heat penetrates two miles deep.

  3. Not going to engulf Earth by teslar · · Score: 4, Informative

    When that happens in an estimated 5 billion years, our sun will be so big that it will engulf the inner planets and most likely Earth.
    Actually, this is incorrect. It will engulf the orbits. The planets themselves will just escape to wider orbits. Except Mercury, Mercury's pretty much buggered.

    More Red Giant trivia at Wikipedia.
  4. ... No. by Cairnarvon · · Score: 5, Informative

    Just because it orbits in 360 days doesn't mean it has an Earth-like orbit.

  5. Earthlike? Not likely... by _mythdraug_ · · Score: 5, Informative
    Earthlike in that it takes approximately the same number of days? Yes.

    Earthlike in any other way? Not likely.

    The Bad Astronomer had a nice examination of this article earlier today.

    1. Re:Earthlike? Not likely... by The+Bad+Astronomer · · Score: 4, Informative

      Well, thanks for the link love. I don't mean to downplay the discovery; it's very cool, and we're one-by-one building an actual catalog of extrasolar planets, which means we can do taxonomy on them. How cool is that? I just want people to understand that there ain't nothing Earthlike about the planet, so that we don't get people running around overblowing this news.

      --
      *** Phil Plait, aka The Bad Astronomer http://www.badastronomy.com
  6. Re:More Exciting by Anonymous Coward · · Score: 3, Informative

    Have a read of the book Rare Earth by Ward and Brownlee ... they postulate that very, very specific earthlike conditions are likely to be necessary for complex life (i.e. above the single-cell level) to evolve. Basically, life here on earth is the culmination of a series of highly improbable happy accidents (as well as unhappy accidents avoided). The case they make is not 100% convincing IMO, but it's still an enjoyable read.

  7. Re:More Exciting by c4miles · · Score: 2, Informative

    Gas giants have solid, liquid, and gaseous phases in their planetary sphere, and don't have a surface as such. 'floating' would pose no mobility problem in such an environment, regardless of gravitational forces. Iain M Banks' 'The Algebraist' revolves around a gas giant ecology.

  8. Re:More Exciting by Jimler · · Score: 2, Informative


    It would not. Light path isn't bend by the atmosphere, but by grabity, and earth gravity i not big enough to bend that path into an orbit. But what you describe is happening around massive object such as black holes. Light passing near horizon can be bent on a orbit which traps the light around for a short priod of time, until the photon hit something and takes another direciton.