Break out the tin foil hatsIf blame must be apportioned (and it must, it must) I blame the Tin Foil Hats. These are the people, often American, who wear a sheet of tin foil wrapped around their heads in the belief that it will shield their brains from mind control rays - alien mind control rays. Chief among the TFH, as they are sometimes abbreviated, is the UFO researcher Michael Menkin, who promotes homemade "thought screen helmets" as a means of blocking mental communication between humans and extraterrestrials intent on abduction. The shame is that loons such as these have given aliens, as a subject for serious discussion, a bad name.
By Nigel Farndale
By Nigel Farndale
Worse, a belief that there might be aliens out there somewhere has become lumped in the popular imagination with embarrassing twaddle such as astrology, psychic reading and crystal healing. And yet it is a perfectly respectable belief to hold, not least because the laws of probability support it. Our planet is, after all, one of about 30 billion in our galaxy, and there are about 100 billion galaxies in the observable universe (there may be other universes, but let's not go there conceptually). Our planet has liquid water and is in what is known as the "Goldilocks zone" of our solar system - that is, it orbits our star, the sun, at a distance that makes it not too hot and not too cold, but just right for life to originate spontaneously. The odds on other planets being similarly blessed are not great: a billion to one against. Nevertheless, these improbable conditions must, in all probability, arise on at least a billion other planets. And we know they can arise because they arose here.
Which brings me to the news that we are now a little closer to finding alien life forms. It was announced on Thursday that Nasa's Spitzer Space Telescope has captured enough light from two planets far beyond our own solar system to reveal tentative evidence of chemicals that are thought to play a role in forming DNA. "We're getting our first sniffs of air from an alien world," one of the astrophysicists responsible for the research said with impressive nonchalance.
This may sound like a namedrop, because it is, but I once had the chance to ask Stephen Hawking about this business of aliens. His answer haunts me still. The human race has been in its present form for only the past two million years out of the 15 billion or so since the Big Bang, he said. So even if life developed in other stellar systems, the chances of catching it at a recognisably human stage are small. Any alien life we encounter will be much more primitive or much more advanced than us. And if it's more advanced, he asked, why hasn't it spread through the galaxy and visited Earth?
"It could be that there is an advanced race out there which is aware of our existence but is leaving us to stew in our own primitive juices," he added. "However, I doubt they would be so considerate to a lower life form. Perhaps the reason we have not been contacted by extra-terrestrials is that when a civilisation reaches our stage of development it becomes unstable and destroys itself."
Cue Mahmoud Ahmadinejad?