Slashdot Mirror

← Back to Stories (view on slashdot.org)

30 Billion Earth Sized Planets?

Posted by michael on from the spaceward-ho dept.

Tha_Chaotic_1 writes "The BBC is running a story about a prediction that there are around 30 billion earthlike planets in the universe. This comes following the discovery of the 100th gas giant outside our solar system. Optimistic?"

10 of 58 comments (clear)

  1. gamma-ray emissions by bofh31337 · · Score: 3, Interesting

    I think this number is a bit high. I'm not sure they've taken into account that solar systems too close to the center of the galaxy due to the "galactic doughnut" effect. Anything to close to the center of the galaxy, in the doughnut hole, would not be habitable due to excess bombardment of gamma-rays.

    1. Re:gamma-ray emissions by Passman · · Score: 3, Insightful

      What you mean is that it would not be habitable by us.

      One of the things that life has shown is it's annoying ability to survive where it should not be. Consider the bottom of the Atlantic Ocean: no sunlight, tempratures hot enough to boil us alive, heavy metals and unique compounds forming a soup toxic to life as we know it. Yet life teems there, hundreds of species of plants and animals.

      If life can adapt to that, why not to a few gamma rays?

      --
      Minne-snow-da: Winter is comming...
    2. Re:gamma-ray emissions by Mr.Intel · · Score: 3, Interesting
      If life can adapt to that, why not to a few gamma rays?

      Poking into the realm of science fiction, one would have to presume one of two things for this to happen. Either these life forms would have some sort of natural protection from such radiation or have developed some technology that protects them. Or their life is based on something other than carbon (silicon?). The reason for this is that all carbon based life is easily damaged by high energy light waves. Indeed, most non-metals tend to break down their molecular bonds when exposed to gamma rays. Either way, despite the tenacity of life, it would require a large leap of faith to assume that this is the case.

      --
      ASCII tastes bad dude.
      Binary it is then.
    3. Re:gamma-ray emissions by Havokmon · · Score: 3, Funny
      What you mean is that it would not be habitable by us.

      Yeah, instead of it being inhabited by little green mean, you'd have large muscular green mean with nasty dispositions (unless you happen to be a hot chick in trouble - hmm doesn't that apply to all guys?).

      --
      "I can't give you a brain, so I'll give you a diploma" - The Great Oz (blatently stolen sig)
  2. Re:How Far Away? by capt.Hij · · Score: 3, Interesting
    With the new world, astronomers say that they have just about finished surveying all the Sun-like stars out to a distance of 100 light-years from Earth.

    Looks like they *think* that they've poked around in a 100 light year radius of earth. Given the extremely poor precision in which distances are measured this may be a bit optimistic.

    Also from the article:
    And if stellar statistics gathered in our local region of space are applied to our galaxy of 300 billion stars, then there may be 30 billion Jupiter-like worlds and perhaps as many Earth-like worlds as well.

    Since our universe is not uniform this may be an abuse of statistics. They've only looked at one very small corner. This is a heck of a Monte-Carlo simulation, though!

  3. Universe by Mt._Honkey · · Score: 4, Insightful

    Not to nitpick, but is should be noted that the article states that there are probably around 30 billion earth-like planets in our galaxy, not in the whole universe. A significant point, considering that there are around 10 billion large galaxies and 100 billion dwarf galaxies.

    Wow, if there are 30 billion in our galaxy, that would make around 300,000,000,000,000,000,000 earth like planets in the known universe. If 1/10th of those are capable of supporting life (a pessimistic view when you consider that at least one out of four in our solar system is capable, not to mention mars and europa), then that's still 30,000,000,000,000,000,000 planets that can support life. If even 1% of those actually have life, and .1% of those have had intelligent life, that's 300,000,000,000,000 planets that have had intelligent life forms in the known universe. Of course, you have to factor in the time spans involved...

    On a side note, MS word spell checker recognizes europium, but not europa.

    --

    Don't Bogart the fish sticks
    1. Re:Universe by p3d0 · · Score: 3, Funny
      If 1/10th of those are capable of supporting life (a pessimistic view when you consider that at least one out of four in our solar system is capable, not to mention mars and europa)...
      Try this:

      "If 1/10th of all mammals on Earth have highschool diplomas (a pessimistic view when you consider that at least 2/3 of the mammals in my apartment have diplomas)..."

      See the problem?

      --
      Patrick Doyle
      I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
  4. Further abuses of induction by ssyladin · · Score: 5, Insightful

    This article contains so much flawed logic, it boggles the mind. First, [t]he latest find is a gas giant and orbits a Sun-like star 293 light-years away. Though how this relates to a 100 light year sphere around earth confuses me. Second, with about 300 billion stars in our galaxy, there could be about 30 billion planetary systems in the Milky Way alone. While the 300 billion stars is correct, a vast majority of them are on the galatic disk or in the galatic core, where the gravity of the densely packed stars would prevent planet formation according to any currently held theory, except maybe Electric Universe. Lastly, most of the exo-solar planets that have been found so far are multiple Jupiter-sized and orbiting so close to the star that it doesn't resemble our solar system, the only one we really know about, making any inferences about the existence of other planets useless and pointless. While 100 exo-solar plants found is a cheer for modern astronomy and a good sign for the likelyhood of ETs, this article uses poor logic to make a bang from a whimper

  5. Hard to say by DeadVulcan · · Score: 3, Insightful

    Firstly, to respond to an earlier post, the article did say "billions of Earths in our galaxy," not in the entire universe. It was the very first sentence, for heaven's sake.

    The biggest question in my mind, with regards to this article, however, is the following statement:

    there could be about 30 billion planetary systems in the Milky Way alone; and a great many of these systems are very likely to include Earth-like worlds, say researchers.

    "Say researchers" is a pretty glib way to support such a big statement. Since current planet-finding techniques can only pinpoint gas giants, I suspect we can really have no idea what percentage of planetary systems contain earth-like planets. So it's this logical jump that is really the issue. And the article is a little thin on the explanation of this reasoning.

    Finally, I would say that a figure that's calculated using sound statistical methods is never optimistic nor pessimistic, it's just that, in this case, the margin of error might very well be something on the order of plus or minus 30 billion.

    --
    Accountability on the heads of the powerful.
    Power in the hands of the accountable.
  6. it's worse than that by Tumbleweed · · Score: 3, Interesting

    There's also a theory that says that you may well need to have at least one gas giant further out from your star to help deflect space schmutz from wiping your species out too early. Since we have 4 very large planets further out from our planet, we've got a lot of gravity wells helping to keep the inner system cleaner than it would normally be. Then again, this may be a rather common configuration - if a star forms and a gas giant forms, then the eddys between the forming star and forming gas giant may just be what turns into a smaller planet. Where's a Wayback Machine when you need one? *sigh*