November 5, 2012 11:58 am
Finding Life on Other Planets May Be Even Harder Than We Thought
An artist’s imagining of an alien asteroid belt. Photo: NASA
Finding extraterrestrial life-as-we-know-it is an incredibly difficult prospect. For starters, we need not only to find another relatively small rocky planet orbiting around a star that hangs light years away. No, that planet must also orbit in the “Goldilocks Zone”—not too close to its star that any water would be blasted away, but not too far that the surface would be frozen and dead. For all that, we’ve actually found a few promising candidates so far. But now, to make things even more difficult, says Ian Steadman for Wired UK, our theoretical bastion of other-worldly life might also need to have an asteroid belt hanging just a smidgeon further out in its solar system. Here is how the thinking goes:
According to the theory of punctuated equilibrium, evolution goes faster and further when life has to make rapid changes to survive new environments — and few things have as dramatic an effect on the environment as an asteroid impact. If humans evolved thanks to asteroid impacts, intelligent life might need an asteroid belt like our own to provide just the right number of periodic hits to spur evolution on.
The persistent peppering of Earth with small-scale asteroids was an important source of raw resources (water, rare elements). Big asteroids provided just enough of a bumpy ride to give evolution a kick.
In his famous Drake Equation, Frank Drake proposed a means of mathematically calculating the number of other intelligent species in the universe. If an asteroid belt in just the right place is a key feature of finding intelligent life, the number of possibilities the equation yields could shrink. (Check out the BBC‘s interactive Drake Equation calculator.)
In a survey of 520 gas giant exoplanets, says Steadman, scientists found that only 19 of them had the right solar system-setup to mesh with the asteroid-belt hypothesis.
More from Smithsonian.com:
Choose Your Own Alien Adventure – The Drake Equation Gets Interactive
Meet Earth’s New Companion Asteroid
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There is a serious problem with the Drake equation – inadequacy of reliable input. Even one incorrectly guessed input variable rendering the output meaningless.
We must always remember the IT mantra of GIGO : garbage in – garbage out.
The very widely publicized possible importance of the asteroid belt as well as a gas giant is certainly of interest.
However, with regard to the wider issue, a very good case can be made for the presumption that, whatever the time-scale, humankind will never encounter extra-terrestrial “intelligent” (I prefer the neologism “Imaginatory” ) life.
Simply because, should we manage to escape (or at least postpone) extinction, the next, non-biological, phase of “life” could well prohibit contacts of this kind between more primitive organisms such as we..
This kind of cosmic censorship provides one possible explanation for the Fermi paradox.
And it is consistent with the pattern of autonomous evolution of technology that is so evident today.
Very real evidence indicates the rather imminent implementation of the next, (non-biological) phase of the on-going evolutionary “life” process from what we at present call the Internet.It is effectively evolving by a process of self-assembly. You may have noticed that we are increasingly, in a sense, “enslaved” by our PCs, mobile phones, their apps and many other trappings of the increasingly cloudy net.
We are already largely dependent upon it for our commerce and industry and there is no turning back. What we perceive as a tool is well on its way to becoming an agent.
Consider this:
There are at present an estimated 2 Billion Internet users. There are an estimated 13 Billion neurons in the human brain. On this basis for approximation the Internet is even now only one order of magnitude below the human brain and its growth is exponential.
That is a simplification, of course. For example: Not all users have their own computer. So perhaps we could reduce that, say, tenfold. The number of switching units, transistors, if you wish, contained by all the computers connecting to the Internet and which are more analogous to individual neurons is many orders of magnitude greater than 2 Billion. Then again, this is compensated for to some extent by the fact that neurons do not appear to be binary switching devices but can adopt multiple states.
Without even crunching the numbers, we see that we must take seriously the possibility that even the present Internet may well be comparable to a human brain in processing power.
And, of course, the degree of interconnection and cross-linking of networks within networks is also growing rapidly.The culmination of this exponential growth corresponds to the event that transhumanists inappropriately call “The Singularity” but is more properly regarded as a phase transition of the on-going “life” process.
The emergence of a new and predominant cognitive entity that is a logical consequence of the evolutionary continuum that can be traced back at least as far as the formation of the chemical elements in stars.
The broad evolutionary model that supports this contention is outlined very informally in “The Goldilocks Effect: What Has Serendipity Ever Done For Us?”, a free download in e-book formats from the “Unusual Perspectives” website.
Comment by Peter Kinnon — November 5, 2012 @ 7:10 pm