Let’s face it, we’d all love to meet an alien. While the notion of a War Of The Worlds-style invasion is a scary one, the possibility of strange, exotic life outside our own planet is a thought that appeals to the curious youngster in all of us.
It’s somewhat depressing, then, that as scientists have discovered more and more about our galaxy, the planets that neighbour our own have gradually been ruled out as candidates for intelligent life.
Mars, once thought to be home to an ancient civilisation living among a network of canals, is now known to be extinct, its core frozen and its atmosphere now a mere wisp of methane.
Venus, alternately thought to be a covered in swamp and desert, and was the favoured setting for works of fiction by writers such as Edgar Rice Burroughs and Ray Bradbury, is a hostile planet of volcanic eruptions and poisonous gas.
But as Professor Brian Cox explains in the final part of his superb Wonders series, life may yet be found tucked away somewhere in our galaxy, if only we knew where to look.
Although the majority of species on our own planet rely on a constant supply of water and sunlight for their existence, Cox demonstrates that some organisms still thrive, even in the most hostile conditions. Journeying to the depths of the ocean – where, the professor explains, the atmospheric pressure is comparable to that of Venus – we’re shown an abundance of aquatic life and vegetation amongst the gloom. In Mexico, there’s a dank cave where, despite the sulphurous atmosphere, strange, bacterial organisms called snottites cling to the rock.
These simple forms of life, existing in the most unlikely places, are evidence that similar organisms may survive even on the most apparently hostile planets. And while the lakes and rivers that once covered Mars are long gone, there remains the possibility that life may exist lurking beneath its surface. Similarly, Europa, the frigid little moon orbiting Jupiter, could be home to a species of bacteria that thrives in its icy wastes, just as it does in the frozen caves of Iceland.
But as interesting as all this is, it’s disappointing to think that, if there is life in our solar system other than on Earth, it probably isn’t any more interesting – or likely to invade us – than the contents of a hanky.
Nevertheless, this final episode rounds off a series that has been as beautiful to look at as it has been informative, and that, as its name implies, has imbued its science with a sense of wonder that is all too rare in documentaries of its ilk. And even if Professor Cox couldn’t bring us news of aliens on other worlds, his series has succeeded in bringing the planets of our solar system to life in often spectacular fashion.
Are there snottites on Mars? Possibly. At any rate, it’s a David Bowie song I’d like to hear.
See our review of the previous episode, Dead Or Alive, here.