Anybody Out There?
By Guy Kahane
These days it seems as if every couple of weeks or so we get reports about newly discovered planets that are ever more similar to Earth. The most recent discovery, planet Proxima b, is the closest planet found so far; Scientific American called it ‘the Earth next door’. Last October, an amateur group of astronomers noticed that the star KIC8462852 was flickering in an odd way, its brightness changing by up to 22 per cent, a much larger change than could be explained by any familiar cause. Some science fiction fans speculated that this might be a ‘Dyson Sphere’—signs of a super-advanced civilization desperately trying to harness energy from their sun. No convincing explanation of this effect has been found so far, and another star, called EPIC 204278916, was recently spotted exhibiting the same mysterious flicker. Then it was reported that Russian radio astronomers recorded a two-second burst of mysteriously strong radio waves coming from a sun-like star in the Hercules constellation.
We know we shouldn’t get too excited. Even if there are numerous Earth-like planets out there, they may all be lifeless. And scientists will probably eventually find perfectly natural explanations for these strange flickers and signals (the Russian report already seems to be a false alarm, caused by terrestrial interference). But still: it’s hard not to anticipate the day—perhaps in the coming few years, perhaps later in our lifetime—when strong, perhaps undeniable evidence of intelligent life elsewhere in the universe will emerge. It sure feels as if that will be an incredibly important discovery. Arthur C. Clarke once said that “there are two possibilities: either we are alone in the universe, or we are not. Both are equally terrifying.” But it’s not that easy to explain why.
