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Earth Science

Earth's Period of Habitability Is Nearly Over 756

xp65 writes "Scientists at this year's XXVIIth General Assembly of the International Astronomical Union in Rio de Janeiro, Brazil agree that we do not yet know how ubiquitous or how fragile life is, but that: 'The Earth's period of habitability is nearly over on a cosmological timescale. In a half to one billion years the Sun will start to be too luminous and warm for water to exist in liquid form on Earth, leading to a runaway greenhouse effect in less than 2 billion years.' Other surprising claims from this conference: that the Sun may not be the ideal kind of star to nurture life, and that the Earth may not be the ideal size."
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Earth's Period of Habitability Is Nearly Over

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  • by frozentier ( 1542099 ) on Tuesday August 11, 2009 @05:43AM (#29020979)
    Depending on who you believe, the Earth will be inhabitable for a billion more years or so, or a couple hundred years.
  • by BradyB ( 52090 ) on Tuesday August 11, 2009 @06:39AM (#29021273) Homepage

    Gorism

  • by AlecC ( 512609 ) <aleccawley@gmail.com> on Tuesday August 11, 2009 @06:54AM (#29021363)

    I doubt strongly that we will develop sufficient transport to evacuate the earth's current population. But the population is currently scheduled to peak around 2100 and then start falling. *If* we can keep civilisation alive until this event occurs, I think is it a pretty good bet that we can taper our population down over the last few millennia so nobody gets left behind. Educated, well off people who know that their children have very good survival chances have been shown to be, on average, remarkably sensible about reproducing responsibly. (Though see current issue of The Economist for an article about how birthrates fall with wealth, but seem to be rising with super-wealth. But the super-wealthy will be the ones with the off-planet ticket).

  • by jozmala ( 101511 ) on Tuesday August 11, 2009 @07:11AM (#29021459)

    Lets put it this way, by that time, technology has advanced a lot. And we probably have colonized rest of the planet system.
    You can put a huge mirror slightly closer to sun than lagrange point (to compensate by gravity the idea of having huge solar sail) Then target that somewhere where extra solar radiation would be useful, outside of earth. Perhaps even, targeting small portion if to its shadow on earth, so that the darkness wouldn't come to its shadow in day light, but simply day being less bright. Anyway There are thousands of different ways of doing that thing. Only thing that could prevent us surviving this would be some other catastrophe for instance a nuclear war, that takes all the options of making such things impossible. By the time its a problem IF modern human civilization is still around then we can pretty much block it, and probably with better method than could be imagine from current technology. With modern technology we COULD make a sun screen should we pool earths resources to that project so that it would be finished within 100 years.

  • by superwiz ( 655733 ) on Tuesday August 11, 2009 @07:11AM (#29021467) Journal
    The idea that technological advance is as inevitable as a law of nature is a fallacy. It usually relies on us getting lucky because somewhere an enabling technology or knowledge was discovered. The only reason Europe emerged from the dark ages is that crusades brought back the Arabic numbers, for example. Gauss once blamed Euclid's not introducing digital numbers and sticking with base-60 numbers of the Greeks for all of the Dark Ages. Roman numerals do not make multiplication table manageable by any accounts, either. Basically, once the enabling technology is stumbled upon, you get a bunch of people in different parts of the world exploring all of its implications. Until then, you pretty much hit stagnation point sooner or later. American Indians never discovered a wheel, by the way. Social forces ALWAYS play catch up with technological state of humanity. As long as we remain the same specie, that is. Moore's Law is already at its limit. The next step is two-prong: parallelism and hybrid (analog-digital) chips.
  • by damburger ( 981828 ) on Tuesday August 11, 2009 @07:40AM (#29021601)

    From TFA:

    âoeThe Sun does not seem like the perfect star for a system where life might arise. Although it is hard to argue with the Sunâ(TM)s âsuccessâ(TM) as it so far is the only star known to host a planet with life, our studies indicate that the ideal stars to support planets suitable for life for tens of billions of years may be a smaller slower burning âorange dwarfâ(TM) with a longer lifetime than the Sun â about 20-40 billion years. These stars, also called K stars, are stable stars with a habitable zone that remains in the same place for tens of billions of years. They are 10 times more numerous than the Sun, and may provide the best potential habitat for life in the long runâ. He continues: âoeOn the more speculative side we have also found indications that planets like Earth are also not necessarily the best suited for life to thrive. Planets two to three times more massive than the Earth, with a higher gravity, can retain the atmosphere better. They may have a larger liquid iron core giving a stronger magnetic field that protects against the early onslaught of cosmic rays. Furthermore, a larger planet cools more slowly and maintains its magnetic protection. This kind of planet may be more likely to harbour life. I would not trade though â you canâ(TM)t argue with successâ.

    Maybe nobody has visited us because, from interstellar distances, Earth doesn't look like a place that could harbour life?

  • by Opportunist ( 166417 ) on Tuesday August 11, 2009 @08:24AM (#29021819)

    I've been laughing my ass off about a friend telling me he bought a house in Italy. Italy! That idiot! In less than half a million years Africa will be all over Italy!

  • by Bakkster ( 1529253 ) <Bakkster.man@NOspam.gmail.com> on Tuesday August 11, 2009 @08:41AM (#29021957)

    Religon making sense, doesn't that destroy the need for faith?

    Not necessarily. An airplane's principle of flight makes sense (air pressure difference provides lift), but you still need to have faith that it your specific plane will be fine and that the pilot is good. It also doesn't prevent people from not putting their faith in airplanes, regardless of them being an incredibly safe form of travel.

    I'd liken religious faith to quantum mechanics. Quantum makes sense, but not according to our normal methods of understanding. It has different rules very different from classical mechanics (secular worldviews), but taken as a whole is consistent.

  • by mcgrew ( 92797 ) on Tuesday August 11, 2009 @09:24AM (#29022487) Homepage Journal

    In our case it won't be pressures, but lack of them. If my ex-wife had been norn a hundred years earlier, she would not have survived childbirth, as she only weighed two pounds. My girlfriend's vagina is so tight that there's no way she could give birth naturally, but she's a mother, having given birth by C-section.

    We are at the point of self-selecting, and we are evolving to be taller. There is no environmental reason for that. In just six thousand years we have evolved to take pleasure in a cat's purr. Evolution continues.

  • Move Earth (Score:3, Interesting)

    by MrKaos ( 858439 ) on Tuesday August 11, 2009 @09:32AM (#29022589) Journal
    I read an article [usatoday.com] about capturing an asteroid into Earth's orbit and using it to slowly adjust the Earth's orbit so that it stays in the habitable zone of the sun.
  • Ice age? (Score:3, Interesting)

    by ivoras ( 455934 ) <ivoras@NospaM.fer.hr> on Tuesday August 11, 2009 @09:46AM (#29022737) Homepage
    Aren't there some much more nearby potential problems that will face the Sun-Earth system by itself (i.e. without meteors from space, etc.), like the Ice Age? Currently, we have passed [wikipedia.org] the interglacial optimum (which happened three to five thousand years ago) and statistically, we are heading toward a Big Winter (popref GRR Martin - "The Winter is Coming" :) ). Technically, we are currently in an Ice Age [wikipedia.org].
  • You can do something (Score:4, Interesting)

    by assertation ( 1255714 ) on Tuesday August 11, 2009 @09:46AM (#29022739)
    Most global problems are exacerbated by over population.

    According to the United Nations, the global population could be as high as 11 billion in 2050 or as low as 8 billion, if the right programs are put in place now.

    Source: PopulationConnection.org [populationconnection.org]

    You can something positive about this without feeling guilty or giving up having children of your own:

    Taken globally, the total fertility rate at replacement is 2.33 children per woman. 2.33 children per woman includes 2 children to replace the parents, with a third of a child extra to make up for the different sex ratio at birth and early mortality prior to the end of their fertile life.

    Source: Wikipedia [wikipedia.org]

    That means if most people limit themselves to just 2 children the global population will stabilize if not slightly shrink. You can also help by telling other people these facts so when it comes time to plan their families they can make a decision that will contribute to a better world for their children.

  • Re:Ice age? (Score:3, Interesting)

    by Ambitwistor ( 1041236 ) on Tuesday August 11, 2009 @10:00AM (#29022929)

    We don't know that we should be heading for a long-term cooling now. We could remain in an interglacial for 50,000 years (e.g. here [sciencemag.org]).

  • by Trails ( 629752 ) on Tuesday August 11, 2009 @10:32AM (#29023359)

    I'm in the same mindset as you.

    Up here in Canada, the Green Party used to have a wiki for their policy that intended to foster debate. On one of their pages, they decried fission. I posted a comment (not an edit, a comment), asking, basically that if the looming problem is global warming, and the waste products of nuclear fission are manageable, how is replacing coal plants with nuclear plants a bad thing. My comment was deleted.

    Kinda stunning.

    There are elements of the Green movement that are irrational, all you have to say is "we must/mustn't do X because it's good/bad for the environment", I consider myself a Green, and I find this behaviour abhorrent. While GP paints with too broad a stroke, imo, the colour is just right.

  • by Abjifyicious ( 696433 ) on Tuesday August 11, 2009 @11:05AM (#29023785)

    Do you even know how much waste you're talking about? Imagine a cylinder 10mm in diameter. A 5mm slice of that cylinder will supply your energy needs for a year.

    Do *you* even know how much waste *you* are talking about? The US alone has accumulated over 60,000 metric tons of nuclear waste from fission reactors. Your figure of a 5mm by 10mm cylinder per year of waste is ridiculous.

    Yes, of course coal releases more radioactive material into the atmosphere. Since we have to store the nuclear waste, *none* of it ends up in the atmosphere.

    Now I'm not saying coal is good, or that nuclear isn't necessarily worth it...but if you want to advocate nuclear power, then stop damaging its credibility with arguments like these.

  • by RabidMoose ( 746680 ) on Tuesday August 11, 2009 @11:19AM (#29023991) Homepage
    I don't understand why you seem to think having radioactivity released into the atmosphere is preferable to having it stored safely at a power plant.

    As for waste, a large coal power plant (under full load) requires about 10,000 tons of coal per day. This doesn't include the energy needed to transport the coal to the plant (via a big ass train).

    And that nuclear "waste" that we've got 60,000 metric tons of? Were it legal to actually build breeder reactors, we could use it to generate more power, and be left with hardly any radioactive waste in the end.
  • by operagost ( 62405 ) on Tuesday August 11, 2009 @11:51AM (#29024463) Homepage Journal

    With the privatization of energy companies, nuclear energy is a disaster waiting to happen.

    What is it about socialized energy generation that makes it safer? After all, the worst nuclear accident in history occurred in the Soviet Union. By contrast, the privately owned (but admittedly, well regulated) Three Mile Island 1 reactor did not release any radiation into the surrounding area and no personnel were injured.

    It's a matter of how the core-values of for-profit organisations manifest themselves in the market, which is essentially to maximize profits.

    Oh, I see. Because the thirst for power in government isn't as dangerous as the thirst for wealth in the private sector?

    Government regulation won't work, since governments core values are to maximize their own survival, and this is primarily faciliated by aligning themselves with profit-maximizing legislation for for-profit organizations.

    You could argue that they don't have to walk the line, and can avoid mistakes, but considering what a wonderful service I'm getting from British Gas right now, I definitely do not want nuclear energy in their "competent" hands.

    OK, so you DON'T think that government is the answer. I don't see any solutions in your post. Here's mine: well-regulated, privately owned nuclear plants. The USA has had these for decades with, as I mentioned, one accident 30 years ago with no injuries or environmental damage.

  • by bs7rphb ( 924322 ) on Tuesday August 11, 2009 @12:07PM (#29024703) Homepage

    Just like being environmentally conscious and opposed to GM crops. Absolute madness. Herbicide-resistant GM crops are fantastic for the local environment - they need much less herbicide use than either conventionally- or organically-grown crops to produce a decent yield, which means more green weeds, more flowers; more bees, butterflies and birds.

    I used to work on the UK GM crop split-field trials, where half the field was conventionally-treated conventional crop, and half was herbicide-resistant crop treated with less herbicide (as designed). The GM side was always green, buzzing with insects, and had noticeably more bird-life; the conventional side was bare earth until the crop came through, then stayed much less verdant. The farmers loved the GM crop, as it needed less work (fewer sprayings) and less costly herbicide.

    The 'environmental' protesters would always ruin the conventional half of the field. They saw the brown, ugly side and thought 'well that must be the evil GM side'. Of course, once half the split-field trial was trashed, the whole trial was wasted. The experiment didn't provide any useful data, and we in the UK are still spraying our fields with herbicide.

    Greenpeace? Wankers.

  • by synth7 ( 311220 ) on Tuesday August 11, 2009 @01:41PM (#29026135)
    Just to expand upon the parent's point: Native Americans most certainly knew of the wheel and applied it where they felt it was useful, however for most tribes it simply wasn't useful. To make it more useful you'd have had to construct decent paths or roads, and the benefits of improved roads would have been of little help save for facilitating wheeled-transport use. It was not that inventing uses for the wheel was beyond them... but that the wheel's continued use requires a level of "buying into" the idea across the entire culture. Frankly, their choice to use canoes and horses was probably optimal for the purposes they wanted to achieve.
  • by RyuuzakiTetsuya ( 195424 ) <taiki.cox@net> on Tuesday August 11, 2009 @04:05PM (#29028845)

    Eventually fissile material will cease being fissile and yet still be dangerous. FBRs are a stop gap and it also allows us to make more out of a given sample of fissile material, but, it doesn't solve the waste problem, it just puts more stops before a given sample of material will become a problem.

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