Hey E.T. Anyone home? Why I believe in life on other planets
When E.T. was first released back in 1982, I built myself a cardboard spaceship and told my mum that I had to go find him, but would be back soon.
I think I mainly wanted to be Drew Barrymore’s character, Gertie but I was also utterly convinced that E.T. was real and that he could “phone home”. I’m certainly not the first person to believe in life ‘out there’ As early as 218 BC, Historian Titus Livius recorded that “a spectacle of ships gleamed in the sky”. That’s more than 2,230 years ago (!) and is thought to be the first suggestion of any kind of alien appearance near Earth.
My grown-up companions all told me there were no such things as aliens and so I became less convinced about E.T.’s existence and eventually gave into to what they were telling me. Fast forward to the present-ish day, and science has yet again come to my aid and restored my faith in there being life somewhere other than on our own planet. But am I just seeing what my inner 5-year old wants to see? Here’s what we know so far.
One of the best lecturers I’ve ever seen, Professor Brian Green said that everything we know about how the physics and maths of space work show that it’s almost impossible for us to be the only life in the Universe. What’s more, now we have the means to see further into space we’re being inundated with images of new planets, suns and solar systems similar to our own. Surely it’s not a question of ‘if’ but ‘when’ we discover life outside our solar system?
We now know that there are planets capable of supporting life
During its 9-year mission, NASA’s Kepler spacecraft discovered a whopping 2,600 planets outside our solar system, many of which could be promising places for life. Of these, a handful are in the so-called “habitable zone” – i.e. it’s not too hot and not too cold and it’s not too near to, or far from its sister sun. You could say it’s the Goldilocks Zone! The best candidate for a habitable planet was Kepler 186f (catchy!). It’s around 10% bigger than Earth and a similar distance from a large star at the centre of its solar system. Kepler 186f (not getting any catchier) is the first planet mass with Earth-like characteristics, and while there’s plenty of research still needed so we can understand more about it, scientists are very excited about this potential Earth-cousin.
Discovering intelligent life is just a matter of time
Many scientists believe that we’ve now discovered all the ingredients that make up the entire Universe. So the Universe is essentially a recipe book where each planet’s recipe is a selection of ingredients from a single list, and in a place as big as the Universe our ability to find another planet made out of the same ingredients as Earth is only limited by how far we can search. And the search is far from over.
All of this makes 5-year old me very happy and call me crazy, but I still think it would be cool if someone’s out there looking for us too. And if they’re able to read this, “I’ll totally help you phone home if you crash land in my back garden!”