A Galactic Brain?

In recent years we have discovered that some our closest neighbors may have planetary systems in orbit around them. Powerful telescopes have detected minute wobbles in the star’s position, suggesting that it is being tugged back and forth by the gravitational pull of a Jupiter sized planet, or in some cases, two Jupiter sized planets. So far about hundred possible planet-bearing stars have been detected.

What are the chances that any of them have planets capable of supporting life? Opinions vary, but the general consensus is that smaller planets with chemistries similar to Earth are likely. (As I write, news comes of water vapour being detected in two of these systems.) How many may have evolved life is much more open. Some believe that, under the right conditions life is very likely to start, others think it quite unlikely. Even if it were only one in thousand, that still leaves millions of possible life-supporting systems in our galaxy alone. And on some of those life may have evolved into intelligence species, who, like us, can look out into the night sky and ponder their place in this huge cosmos.

They would see a view very similar to ours. And they too will begin to detect other planets. And begin to look for those that may have sustained life, and possibly intelligent species.

If our own technologies have now reached the point where we can make rough guesses at the number and size of the major planets orbiting some of our closest neighbors, what will we be able to deduce ten years from now? Or fifty years? What may a far more advanced species be able to detect from a distance about life on its neighbors? Might it even detect the telltale signs of intelligence? Might it then seek to make contact?

Let us assume that Einstein’s Theory of Special Relativity is correct, and it is indeed impossible to transfer information faster than the speed of light. The closest stars are around 10 light years away. Any message sent to them would take 10 years; and any response a similar time. Each interchange of any communication would take 20 years. That is in the unlikely event that advanced intelligent species were to be found so close by. More likely they will be much further away–hundreds of light years distant.

The slow building of a dialog would take thousands of years. It would be a collective effort of the species. Much as the building of the great gothic cathedrals of Europe were–no one present at the start of a cathedral ever lived long enough to see its completion. But in cosmic time, a thousand years is a tiny fraction of galactic history, about the same fraction of time as speaking one sentence takes in a human life.

There may be a network of who knows how many intelligent systems out there in our galaxy sharing their discoveries with each other–a growing galactic brain.

Who knows where their conversation may have led, or what wisdom we will meet when we join in?

Date created: 12-Dec-05