SETI – A better way?
In a nutshell: point your listening devices toward the centre of the galaxy and listen for coordinates of other intelligent civilisations.
Our solar system is in an arm of our galaxy which contains something like 500,000,000,000 stars of which we can see about 3,000 with the naked eye. When we look toward the centre of the galaxy on a clear night because we are in amongst it we see a strip of glowing haze we call the Milky Way which is in fact a lot of stars very far away all merged together.
Statistically, there is a good chance that other life has evolved in our own galaxy. In fact from what astronomers have found in the way of Earth-like planets orbiting nearby stars it looks like there is a very good chance that there are many other civilisations more advanced than our own.
SETI (at least according to Carl Sagan’s 1994 book, Pale Blue Dot) scans the sky listening for radio signals on a frequency they have assumed other intelligent life would also choose to broadcast on. Something to do with the hydrogen line. Anyway, they’ve got a lot of sky to cover and the combination of limited resources, assumptions of alien technologies and narrow frequencies they’re not having a lot of luck. The most intriguing encounters they’ve had (at least up until 1994) have all been from the direction of the centre of the galaxy. They weren’t able to pick up the signal again and it’s possible that it may have been temporarily amplified by a gravitational field or whatnot. Either way it didn’t count.
If you make the assumption that there are many, many intelligent civilisations then I would suggest that it would be a good starting place to point your listening devices toward the centre of the galaxy for the following reasons:
- It’s the one benchmark we will all know of
- If someone broadcasts a strong signal toward the centre then someone on the opposite side is likely to pick it up
- All each civilisation needs to do is broadcast a list of coordinates of all known civilisations and when a new one comes on board they append their coordinates to the list
- You then point your listening devices and transmitters at the other coordinates in the list
Now, keep in mind that I know next to nothing about sending radio signals through space (other than the fact that it takes many thousands of years travelling at the speed of light to even reach the centre) but if, in fact, it is possible to broadcast across these distances then it’s possible someone else may have had the same idea and we may pick up some handy information broadcast 60,000 years ago.
It’s entirely possible too that civilisations more advanced than us may have discovered faster ways of conveying information than radio waves (yes, yes, I know, nothing beats the speed of light) and would consider it an absurdity to revert back to the equivalent of carrying a letter by hand halfway around the world.
