That’s a difficult question to answer but the launch of NASA’s Kepler mission will go part of the way at least to discovering if there are any planets similar to the Earth out there.
The BBC asked some experts for their thoughts on the existence of other life and their answers are varied.
I reckon that the question should really be: is there anything out there?
Life has been found in so many environments here on Earth, some utterly extreme and seemingly inhospitable, that it seems inevitable that somewhere in the vastness of the universe other life will exist. Where it does exist, it will certainly be very different from we humans. It may be so different to us that we don’t even recognise it as life.
Will any alien life found out there be intelligent and more advanced than us? Well, given that at times our behaviour doesn’t really seem either intelligent or advanced, yes it probably will be. But again its intelligence could be so radically different to ours that we fail to recognise it.
Any life that does exist in the wider universe will have evolved to suit its environment. Unless we find an exact match for our planet somewhere you can be pretty sure that the likes of the cantina scene portrayed in Star Wars will be way off the mark. And prospective Captain Kirk’s can pretty much forget meeting beautiful alien women who want to practise the strange human act of kissing…