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The Galaxy May Have Billions of Habitable Planets

The Bad Astronomer writes "A recent astronomical report (abstract in Science) came out stating that as many as 1 in 4 sun-like stars have roughly earth-mass planets. But are they habitable? A simple bit of math based on some decent assumptions shows that there may be billions of potentially habitable worlds in the galaxy. '... astronomers studied 166 stars within 80 light years of Earth, and did a survey of the planets they found orbiting them. What they found is that about 1.5% of the stars have Jupiter-mass planets, 6% have Neptune-mass ones, and about 12% have planets from 3 – 10 times the Earth’s mass. This sample isn’t complete, and they cannot detect planets smaller than 3 times the Earth’s mass. But using some statistics, they can estimate from the trend that as many as 25% of sun-like stars have earth-mass planets orbiting them!' Getting to them, of course, is another problem altogether..."

6 of 380 comments (clear)

  1. Fermi's paradox. by Hatta · · Score: 5, Insightful

    That would seem to make Fermi's paradox even more troubling. My bet is that abiogenesis is vanishingly improbable. It seems pretty reasonable to be fairly optimistic about every other term in Drake's equation.

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    1. Re:Fermi's paradox. by IndustrialComplex · · Score: 5, Insightful

      I wonder what happens if we continue to expand our knowledge about exoplanets at the current rate but we don't discover life on another planet by the year 2100. Fermi's Paradox bugs the hell out of me. I can't see how we are unique... but I also can't see why the evidence of other civilizations wouldn't be obvious.

      There are loads of reasons.

      1. How long did it take for US to come about? That's a fairly long period of time for a planet to remain habitable. Cut that time down, and you drastically reduce the chance that something like 'us' will come about.

      2. What good is intelligence to life? To us, it is necessary, to life? Not really. Algae and bacteria do just fine (and bacteria in some sense can be considered immortal!) Life COULD be plentiful, and intelligent life could well be so rare that it is unique.

      3. Consider what we are able to see. We can basically see forms of electromagnetic radiation. That's not too useful for picking out little bits of information that would clue us in to someone else sending out information. Our emmanations are already decreasing (if considered per-capita) We can get more done with less power via directional antennas, better electronics, and now, fiber and direct access communications. We might just not see them.

      4. Interstellar travel cost compared to opportunity is well... astronomical. Barring imaginary physics, the only point to go to another planet/star is to colonize it.

      Think about it, we human beings are the absolute kings of colonization. We have set foot and abode on nearly every inch of this planet in some form or scope. And even if you argue that our grasp in some areas is tenuous, it certainly isn't due to lack of drive to colonize. We ARE wanderers and travelers, but to even consider something like interstellar travel is daunting to us. Is it so surprising that something which would restrict a human from traveling would also daunt another form of life?

      It's not too much of a stretch to consider that our existance is every unique even without resorting to some sort of religious justification.

      If it took our planet 4-5 billion years to produce 'us', and the universe is only 14 billion years old, we aren't dealing with much time for starting over. A single asteroid collission at the wrong time and the death of a human progenitor could very well mean 4 billion years of life development resulted in no intelligent life on Earth. It is not some sort of evolutionary goal.

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    2. Re:Fermi's paradox. by callmebill · · Score: 5, Funny

      Could be God. Consider: what is more unlikely? That before time there was an infinitely dense concentration of something that burst, creating everything we observe? Or that before time, there was something else that said, "I'll make something today" and created everything we observe? I don't consider either one more or less plausible than the other.

    3. Re:Fermi's paradox. by Chris+Mattern · · Score: 5, Insightful

      It seems pretty reasonable to be fairly optimistic about every other term in Drake's equation.

      Actually, there's one other you can be pessimistic about, and it has pretty depressing implications for us: the fraction of technological societies that get off-planet. Two big humps here:

      Agression: Any species that fights its way to intelligence and technological dominance of its planet will be about as aggressive as we are. A species that is not good at stepping over what's in its way to get the resources necessary for survival is a species that doesn't survive. This raises the question: can a dominant technological species avoid destroying itself with the advanced weaponry it develops (or even inadvertently by triggering an ecological collapse) before it gets off-planet? The jury is still out on whether we'll manage that...

      The Lotus-Eater Problem: About the time a dominant technological species starts to develop the necessary skills to get off-planet, it likely also start to develop the skills necessary to create *really good* simulations of reality that are "just like the real thing." Can a culture avoid the lure of just abandoning themselves in fantasies which can be made more exciting and fulfilling than anything in the real world?

  2. Re:NASA by jokermatt999 · · Score: 5, Insightful

    Do you have any numbers to support this? Although government programs generally are horribly inefficient, do you have any actual data indicating that NASA is just as bad? You seem to be relying on the assumption that government programs are always wasteful inefficient messes to the nth degree. Private spaceflight seems like an interesting idea, and I know there are several companies already working towards it, but reaching another star is a long, long, long term investment. It seems to me that government funding is actually useful in cases where there is no immediate return for the investors. Otherwise, you're essentially relying on philanthropy, no?

  3. Re:NASA by Unordained · · Score: 5, Insightful

    Government programs are /always/ plagued by waste and inefficiencies.

    a) Private, commercial ventures are also always plagued by waste and inefficiencies. Humans are involved. You get what you get.
    b) Just because there's waste doesn't mean it's 95% waste. That's like saying that because lightbulbs emit both heat and light, they're incapable of ever illuminating anything.
    c) Grandiose statements like this one, common on the right, are faith-based attacks. It's common sense. Everyone knows governments waste. Everyone knows governments are nothing but wasteful bureaucracies. It's obvious. Duh. The only good government is a tiny one. But not nonexistent, as that might be seen as disparaging the founding fathers.

    The underlying assumption is that you can only trust someone who wants to take your money for his own profit, because anything else is too good to be true. But not too much profit. So you can only trust someone who wants to take your money for his own profit in a suitably competitive market. You only trust greedy people. And then ...

    The only reason why they can sometimes get things done is because they have infinite money from stealing from taxpayers.

    d) No. They're not stealing. We're pooling our moneys to achieve a common goal, as we've agreed to do, through the system of laws we've previously agreed to. If you don't like it, go live in France. (I can say this because I got tired of being told to live in France when I bitched about our new motherland security overlords after 9/11.)

    Government restrictions.

    e) That's what it *does*. That is the function of government. All freedoms not taken away, we keep. You're complaining that they're doing their job? If not, we need to know the specific restrictions you disagree with; honestly, I trust them to have a better idea of what restrictions we need than I trust you. They have thousands of people looking at what can go wrong when some private individual decides it's perfectly safe to shoot a rocket off from his back yard to go colonize Mars. And those thousands of people? They're just private citizens, like you and me, raised in the same country, under the same flag, learning the same constitution, going to the same backyard BBQ's. They love freedom too. Freedom not to be blown up because of their neighbor's stupid belief that freedom only means something when they can be perfectly reckless.