Is This How Aliens Could Rule the Universe? Theories on Extraterrestrial Domination

Is This How Aliens Could Rule the Universe? Theories on Extraterrestrial Domination

If Sci-Fi and Hollywood blockbusters have taught us anything, it’s that when the inevitable alien invasion occurs, it will be loud, brutal and fairly unpleasant for most of us. Our new interplanetary overlords will strip our planet of its resources and show no remorse for humankind. 

But let’s move away from science fiction and consider science fact. What do the leading experts in the field think about the possibility of alien invasion? What are the odds that aliens actually exist? What would the aliens look like? And what method would they use to pop by? 

This edition of BBC Earth’s Weird Science investigates the likelihood of alien life… and potential attack.  

What are the chances? 

Our sun, hanging daintily in the centre of the solar system, is a single star. Our galaxy (the Milky Way) has a mere 400 billion additional stars, all doing a similar sort of thing, with a potential 6 billion Earth-like planets orbiting them.1 And once you consider there could be 2 trillion other galaxies in the universe, then you’re suddenly dealing with numbers so huge they’d even make a mathematician cry.

With billions of potential receptacles for life spinning out there in space, surely at least one of them is inhabited? And if that were possible, would these potential life forms be capable of extinguishing life elsewhere?

The Nobel Prize-winning nuclear physicist Enrico Fermi2 was puzzled that alien life had not been discovered yet. He formulated the Fermi Paradox to describe this apparent contradiction: there was no scientific evidence of extra-terrestrial life, but the probability that it existed was high. Solutions to the paradox range from the theory that alien life may not be advanced enough to make contact yet, to the suggestion that aliens maybe don’t want to have anything to do with us.3 Rude.

In 1961, astronomer Frank Drake created an equation to estimate the number of alien civilisations that are close enough for us to have heard from: N = RfpncflfifcL.4 The latest calculations, using a variation of the Drake Equation, suggests that the odds of us being the only intelligent life in the Milky Way are between 53 and 99.6 percent.5 There are too many unknowns to calculate anything more accurate.

So, in short, there might be intelligent life out there or we might be all alone. Some astrophysicists believe alien life of some kind could be right on our doorstep, while others are pretty categorical that the creation of life on our planet was a freak occurrence that could never be repeated elsewhere.

Would they have the traditional grey skin and big eyes? 

But if there is life out there, what would it look like? We’ve all heard stories of close encounters – usually on a rural road somewhere in the American Midwest – where the aliens witnessed tend to have a fairly uniform look. Grey skin, big eyes, no fashion sense at all.

But is there any logic in aliens looking like this?

The elements that make up life on our planet (nitrogen, hydrogen and oxygen) are widespread throughout the universe. So, this would suggest that, if these conditions are replicated elsewhere, life, in some form, could emerge.

However, we also know that whilst life on our planet began relatively soon after Earth was formed, it evolved in many different ways. Once upon a time, the whole place was teeming with dinosaurs – but when they died out, they weren’t replaced with more dinosaurs. Instead, a whole new range of creatures evolved, suggesting there’s not one, singular, optimum form for life on Earth to take. A massive variety of creatures can exist and thrive on this planet, and just as readily die out and vanish.