It's been 50 years since Sputnik 1 began the age of space exploration. Rather than a diversion from Earthly problems, going into space may be one of the best things we can do to save our planet, and ourselves.
I love our planet. I love its trees, its mountains, its oceans, its big beautiful skies and its extraordinary diversity of life. What we have on this world is precious - it's worth cherishing and nurturing.
But that doesn't mean I think that travelling beyond this planet is a waste of time or resources; or that I think we should instead focus on getting our world right before venturing into space. That's just plain silly: did we fix Europe before embarking for the Far East and the Americas? Did we perfect an idyllic nomadic society before leaving the African plains? Waiting to get our “house in order” will achieve nothing but guarantee the demise and eventual destruction of our planet, our ecosystem and our species. Going into space is one of the best things we can do to save our world, and ourselves.
It's in our nature to venture out: since the dawn of our species, we have explored, adapted and expanded. In doing so, we have become the most powerful creatures on Earth, capable of splitting the atom and affecting the climate. Like a teenager experiencing the first flush of hormones, we have felt powerful and invincible - then slowly grown aware that our behaviour and newfound strength could harm others.
It's because of our extraordinary success, our ability to harness resources and bend them to our will that we are encroaching on our neighbours. We live in a closed system - the planet Earth - but often behave recklessly as if its resources are limitless. In the past, we've overcome these constraints by expanding into new territories.
The solution is not to abandon modern industrial civilisation: we're not going to give up our cities or technologies. In fact, without the large-scale mechanisation of industry, transport and agriculture, we would be unable to feed our large and growing population. Going “back to nature” may sound romantic, but would consign billions to starvation.
The first thing to do is reduce our impact on the planet: make technologies more efficient and our cities, transport systems and industrial processes less damaging to ecosystems. We rely on the web of life to sustain us: we need bees to pollinate, trees to make oxygen and worms to aerate the soil, or we would swiftly perish.
And after that? Do we mandate population controls? Do we nominate an arbitrary age at which people need to “retire”, as in the dystopian fictional vision of the film, Logan's Run? Because populations will continue to grow, especially as child mortality rates fall and science finds ways of extending human lives. The logical thing to do is to expand beyond Earth: to build colonies on Mars, floating habitats in Earth's Lagrange orbits, mines on the Moon and the asteroids, and expand deeper into our Solar System.
It may sound unappealing to some. But so was the prospect - just a few centuries ago - of a long and arduous journey across treacherous oceans in cramped conditions, only to arrive in a harsh and unforgiving wilderness where conditions were difficult and starvation was a real possibility. And yet, tens of thousands of people set off for Australia and North America, among many other places, in search of a new life. Thousands perished. And yet, more came.
We need to expand into space because Earth alone cannot sustain us. Space provides a pressure valve, but exploring it will also ensure our survival. Because one day, a massive calamity will befall our world - an asteroid strike, ice ages, supervolcanoes, solar bursts or nuclear war - and we may disappear, or our civilisation fall.
Some ask: so what if humans pass into history? It's not just a tragedy for us, but also one for nature. Without us, there is no one to witness its infinite beauty; no one to marvel at a sunset, revel at a mountain view, or thrill to the breaking of a wave on a beach. As the late astronomer and author Carl Sagan once said, "we are a way for the universe to know itself".
But we also deserve to continue because we have created things greater than ourselves. Not only scientific and engineering knowledge, valuable as this is - we have also created new and beautiful ways to see the world through art, music, literature and performance.
Think of the plays of Shakespeare, the concertos of Bach, the philosophy of Confucius, the epic poetry of Virgil, the suiboku ink painting of Shubun, the fado laments of Amália Rodrigues, the morality tales of Javanese wayang kulit shadow puppetry, the Islamic calligraphy of the Diwani Al Jali style, the novels of Cervantes, the harvest bhangra dances of Pakistan, the rhythms of the didgeridoo, and anything by Leonardo da Vinci.
Even if the cosmos is brimming with other advanced civilisations, we still deserve to be here. Nature in its diversity has made us as we are: we too are children of the universe, and have something to contribute.