BBC Focus magazine are running an interesting competition at the moment, to write an article on the subject of ‘the science that will transform our future’. As I write for a living I’m not eligible to enter, but things like this are always good practice so I thought I’d play along anyway. Here’s the result.
It’s tempting to think of the ‘science that will transform our future’ as some kind of revolutionary technology, like the home robot servants we’ve long been promised or home-grown replacement organs. But I think it will be the fulfilment of already existing technologies: those searching for extra-terrestrial life. I’m talking about microbes rather than little green men, but I think even this discovery would be enough to change our viewpoint.
Uniqueness is a trait we often like to ascribe to ourselves, but we’re also longing to belong, and there’s nowhere this dichotomy is exposed more than when we consider our place in the universe. All evidence so far has pointed to us being perfectly unique; we’ve haven’t found intelligent life and it hasn’t found us. Heck, we haven’t even found basic life.
For a long time it was assumed this was in large part due to the uniqueness of our position; we are perfectly placed around a nice, stable Sun and enjoy abundant liquid water beneath a protective atmosphere. But, as the latest space telescopes and missions repeatedly prove, this is not such a privileged position after all. The Kepler Space Telescope is spotting ever more ‘Earth-like’ planets, with Kepler 438b the current best candidate for a twin planet. To date, less than 20 true twins have been identified, but the speed of discovery is ramping up, with the launch of the Transiting Exoplanet Surveying Satellite in 2017 and the James Webb Space Telescope in 2018 set to continue the trend. NASA currently estimates there are at least at least 200 billion Earth-like planets in our galaxy.
The telescopes scour for planets by detecting the slight dimming of distant stars’ light as bodies cross in front of them, with newer models set up to probe the possible atmospheres of discovered planets and search for elements indicative of life’s processes. So far, the key elements that make Kepler 438b exciting are that it’s likely to be rocky, and at the right distance from its star for liquid water to flow. At 470 light years away however, we’re unlikely to be able to drop in on any potential neighbours any time soon.
But we might not need to go so far to find life. There are plenty of candidates within our own solar system. There are quite a few checks on the list before we can come close to announcing we’ve identified extraterrestrial life, but the recent discovery of ancient oceans on Mars have prompted NASA chief scientist Ellen Stofan to proclaim: “I believe we are going to have strong indications of life beyond Earth in the next decade and definitive evidence in the next 10 to 20 years.” While Mars’ oceans likely dried up millions of years ago, there may be water elsewhere in our solar system, with the best candidate being Jupiter’s moon Europa. Importantly, the ocean of Europa, sitting under a thin shell of ice, is thought to have existed since the Moon’s formation – giving life time to evolve.
Europa also isn’t a dead world like the Moon or Mars. The mighty pull of Jupiter heats the surface, likely promoting dynamic volcanism, creating environments similar to those where some of the most basic life on Earth thrives. The ocean also erupts periodically through the surface of the ice, potentially allowing a passing spacecraft to sample the chemistry of the water. Missions to do just that have been touted for more than a decade, and while preliminary approval has been granted, the promising Europa Clipper mission languishes amid fickle budgets.
What if it were to go ahead detect signs of life in the waters of Europa, fulfilling NASA’s prophecy? I think it’s a discovery that will mean different things to different people, but it will mean something to everyone. The religious may have to expand their definition of god to include a creator that hedges his bets by seeding hundreds of gardens of Eden. The scientific will study what different forms life can take and where and how it can arise, expanding the search and clocking up the numbers of inhabited worlds. For me, it would mean that the universe is itching with life and bursting with potential. And for everyone, it should at least answer the question of whether we are alone in the universe.