Why are we ‘Looking for Aliens’?

The idea that there might be alien life elsewhere in the universe has captured the imaginations of generations of scientists, writers, artists and….well pretty much everyone! Science Brainwaves has a fantastic *free* lecture coming up on Friday 8th November, where Dr Simon Goodwin will describe how astronomers are looking for life on other planets, and what it might be like. So without giving away too many spoilers I thought it would be the perfect opportunity to find out what got our ancestors thinking about aliens and what we might do if we find them….

A 17th Century illustration of the heliocentric system suggested by Copernicus (by Andreas Cellarius from the Harmonia Macrocosmica ,1660) Picture from Wikipedia
A 17th Century illustration of the heliocentric system suggested by Copernicus (by Andreas Cellarius from the Harmonia Macrocosmica ,1660)
Picture from Wikipedia

It’s difficult to say (or at least difficult for me to say, with my limited resources and time!) when people first started thinking about the possibility of life on other planets. However, it’s fair to say that big astronomical discoveries have probably captured people’s imaginations throughout the ages – in the same way that the moon landing got everyone talking about little green men. One such breakthrough is the ‘Heliocentric Revolution’. Heliocentrism is the concept of the solar system with the sun at the centre instead of the earth, an idea that has been around since at least 3rd century BC. However, it was Copernicus who revived the idea in the 16th Century, which was expanded on by the works of Kepler (who calculated the orbits of the planets) and Galileo (who observed other planets by telescope). The spread of the idea that earth wasn’t the centre of the universe must have made our ancestors wonder what else could be out there. Earth was no longer special, just another planet orbiting the sun, so why shouldn’t there be other life filled planets like ours?


alien contact
Top left: The Voyager Golden Record
Bottom left: The Pioneer Plaque
Right: The Aricebo Message (decoded and coloured)
All pictures are from Wikipedia

So far we’ve obviously not had much luck in finding life, but it’d probably be prudent to think about what we’d do if we do find it – especially if it’s intelligent. Stephen Hawking has been heard to offer an opinion on the subject:

“If aliens visit us, the outcome would be much as when Columbus landed in America, which didn’t turn out well for the Native Americans,”

“We only have to look at ourselves to see how intelligent life might develop into something we wouldn’t want to meet.”

Not the most optimistic of outlooks, but he’s got a point. Several attempts to contact alien life have been made by astronomers, but have they given away too much information? In 1973 the ‘Pioneer Plaque’ was sent out on the pioneer 10 and 11 spacecraft, followed in 1974 by the broadcast of the ‘Arecibo Message’ (both pictured right). A slightly more artistic message was sent out in 1977 on the ‘Voyager Golden Record’, which contained information on the sights and sounds of earth. It’s quite romantic to think that if there messages reached intelligent alien life that they might just pop in for a cuppa to say ‘hi’, but the consequences could be a lot worse if the aliens were hostile (and if you’ve got a flair for the melodramatic).

As a microbiologist I can’t help but be a little cynical about grand ideas of intelligent life. At the moment we’ll probably be lucky to find some basic single celled life – which I’ve heard doesn’t tend to be all that talkative (but which as a microbiologist I would find much more exciting anyway!). Anyway, who am I to say what we may or may not find (with all the experience of a 3rd year astrobiology module) – come and hear it from the expert at Science Brainwaves’ free Looking for Aliens Lecture!*


*did I mention it’s free? 😛