The Earth we live on was formed from a cloud of dust and ice, heated by a massive ball of compressed hydrogen that was the early Sun. Somewhere along the four billion year journey to where we are today, our planet acquired life, and some of that became us. Our modern brains ask how it all came together and progressed, and what shaped the pathways it followed. Was life, and the design of the Earth itself, more or less pre-ordained, a chain of chemical reactions and physical laws that just behaves that way when you start out with a given chunk of matter in a our particular universe? Or was there something more special involved? We don’t know yet, but we do know how to find out.
We can predict where that long evolutionary path is headed next. It is clear that the Earth, and its life forms like us, are not finished changing. Time passes relentlessly, carrying us forward into the future while we tame ignorance with hope, and ask of nature profound but difficult questions. Will humankind survive, and will our species grow and improve, eventually to move outwards from the Earth into a fabulous destiny in the wider universe?
We have already progressed to the point where we know that planets around other stars are commonplace, and it is almost impossible now to imagine life is a phenomenon that is unique to Earth. Somewhere out there we may meet other living things, and some of them may be like ourselves. At least a few will be more advanced in their technology and their societies; just think what we could learn from them. But the vast distances involved, the costs, the risks, and even hurdles like pollution, global warming, human conflict, and resource depletion, look pretty formidable. We can’t rule out the possibility that life on Earth, at least the human component of it, has no destiny at all beyond decline, failure, and ultimately extinction. Some would say that it is not just possible but actually probable that human civilisation will not last another thousand years; others think that we will muddle through somehow as we have up until now, forever, until we become omniscient and immortal.
How we wish we understood our place in the Universe, how our brains evolved, what the future holds, and what our chances of survival are! There is no oracle that will tell us, but we do have ways of peering forward and backward in time to piece together the evidence that may eventually lead to a complete picture. What stands out amongst these is exploration: using technology to see new things or to understand old things in a new way. Those of us now growing old witnessed an unprecedented leap forward in the last century, including pioneering journeys into space where we have found new frontiers on other worlds.
However, there are signs today that we are losing some of the momentum we once had. Astronauts have never gone back to the Moon, where they briefly walked before most of today’s scientists were born, and we are really no closer to achieving the first steps on the surface of Mars than we were 50 years ago. Some things have changed – that footfall, when it happens, may well be that of a woman, perhaps even one from India or China, when it finally comes to pass.
But will we go forward at all, or will civilisation collapse under the weight of rising populations on a crowded world with rising seas, droughts, and wars, before we ever understand our place in space? On the face of it, the history of the first half-century of the space age gives us very few clues about what will happen in the next half. But now, living on the Moon, or putting human explorers on Europa or Pluto, is no longer so much about inventing new technology, although some of that is needed of course, as it is about generating popular and political support. If we want to look for life below the surface on Mars, for example, in engineering terms we know how to do most of it already. Soon, we will even be able to send robot spacecraft to explore those Earth-like planets around other far-off suns, even though the engineers and scientists who build the probes may not live long enough to see the data.
It is tempting just to extrapolate the recent history of Earth observation and planetary exploration from the last century into the rest of the present one, and then the prospects look pretty exciting. But much of the recent leap forward was driven by the newness of it all, and underpinned by the resources being poured into globalisation and the Cold War. Things have changed, ambitions have cooled, and the realistic view forward is perhaps less wonderful. Do we have the time and the will to devote precious resources into understanding our origins, and can new technology overcome our problems and safeguard our survival? Or will introversion lead to decline and eventually extinction? In my career of planetary exploration, involving missions to all the planets of the Solar System, I have come to understand these questions much better, but that is not the same as knowing the answer. We’re on a knife edge, but we have choices, and we have opportunities.
Featured image credit: Moon & Space by Tydence Davis. CC BY-SA 3.0 via Wikimedia Commons.