Why haven’t we detected any evidence of alien intelligences yet? The wallpaper on one of my computers is the composite picture NASA published in 2000 of the entire earth at night. The amount of light visible from space is at once beautiful and intriguing, and it makes me wonder how much energy we waste by unintentionally beaming it into space, whether it is light, infrared radiation (heat), or radio waves. Looking back through human history, it is clear that, as a species, we used comparatively little of our planet’s resources before the industrial revolution, and I suspect the view from space back then showed very little human-made light, if any. Then I contemplate the probability that, in the absence of any great new energy-producing technology (fusion?), we will run down our available fossil fuel sources over the coming decades, driving the price up to the point where fewer and fewer people and organizations can afford to use and waste energy as we do today. In another century or two we may be conserving energy to such an extent that we will have to stop our light, heat, and radio waves from dissipating into space, and the planet may return to the way it appeared before the industrial revolution. This brings up some interesting questions about our universe.
As we have searched the skies for other planets, especially those capable of supporting life, and developed ever more sensitive and sophisticated techniques for receiving and identifying signals from alien civilizations, we have met with no success. It seems logical that, with many billions of stars out there, probably millions with planets, and at least thousands with conditions that would support life, that the phenomena that produced intelligent life on Earth would have occurred in other places as well. Still, we have only been sending signals to the universe for less than a century ourselves, and that is a very short time in the scale of the cosmos. Is it possible that there are many intelligent civilizations out there, but that almost every intelligent race evolve through a time when they discover their planet’s energy resources, burn most of them off in a century or two, and then learn to consume energy so efficiently that they radiate virtually nothing into space thereafter? Are intelligent civilizations only radiating in any detectable way for a century or two of their histories, and do their planets appear dark and uninhabited before and after that (cosmically) brief period? Does this mean that there could be countless intelligent civilizations throughout space but that it is extremely rare that any two of them were radiating electromagnetic energy into space at any detectable level at the same time, or that they became aware of other intelligent life at that point in their histories? Is this why we continue to detect no evidence of intelligent life in the universe, even as our own electromagnetic signals are a hundred light years out and propagating away in all directions at the speed of light?
Alternatively, could we be the first to develop radio-related technologies in our corner of the universe? Someone has to be first, right? Or are we last, and quite late compared with other intelligent species, such that other civilizations’ radiation has faded into the cosmic background long before we became aware of such things? Should we be thinking of different ways to detect other intelligent life forms outside our solar system, since looking for radio and TV signals may not be very effective? There is much creative and scientific work to be done, obviously. There is a high probability that, if we could contact other intelligent life forms in the universe, we could learn much from them that would help us overcome our current and future problems. Of course, as energy costs rise due to increasing cost of obtaining it from the earth, we will have to increase our efficiency and conservation efforts, and the night side of the Earth will become darker. Eventually our planet will look uninhabited to someone far away, or even within our own solar system.
In the meantime, we certainly cannot learn too much, and education – public education for every individual – is essential if we are to continue to thrive through the coming decades. Educated people have fewer children, and make other choices that are more sensible in the limited environment of our mother planet. Also, educated people will bring forth the scientists we will need to develop new science that will hopefully help maintain our comfortable lifestyles and bring them to more and more people. I urge you to support real public education, available to all, as opposed to private schools that promote elitism and weaken public schools. We need many smart people, as educated as possible, if we are to avoid a decline in our standards of living as energy costs rise over the coming decades.
As always, I welcome your comments. – Tim