On Saturday afternoon, Neil Armstrong, the first man on the moon, died in Ohio of heart problems that came following bypass surgery. He was 82.
His death has struck home the failure of mankind to build on the legacy of exploration that his generation left us. Just 24 men have travelled beyond low Earth orbit, and just 12 have set foot on an extraterrestrial surface. Of those 12, eight remain, and none were born after 1935. Space travel is an old man's game, it seems.
Coming so soon after the success of the Mars Science Laboratory's mission – when NASA landed a nuclear-powered, laser-armed, one-tonne rover on the red planet – all eyes have naturally turned to the only other planet in the solar system which humans could realistically walk on. (Mercury and Venus would kill you in seconds, the gas giants are, well, gas, and Pluto is so cold oxygen freezes.)
Martin Robbins, for instance, writes in the Guardian:
Curiosity made us what we are: the instinct that makes us click an interesting link on Twitter is the same force that built our cities and hospitals and carried us on rocket ships to the moon. It may not be rational, but we didn't get where we are by being an entirely rational species – we did it by trying things, and failing pretty much most of the time. It's time for someone to step up and show us all that we still have that drive, that when we have the guts to unleash that curiosity – and the guts to fail – we can still achieve greatness. Neil Armstrong's death is a wake-up call, a challenge to our generation. We can go to Mars, and it doesn't need a miracle: we just need to decide to go.
But no matter how impressive the trip to the Moon was, we mustn't forget that it was as much a product of imperialistic showmanship as an urge for exploration. America went, not to indulge their, and our, curiosity, but to shove a big, lunar, stars and stripes in the face of the Russians.
That doesn't lessen the magnitude of the achievement, but it does put a question mark over the idea of repeating it.
We know we can put people on Mars. The technical aspects are tricky, but not much more so than putting an SUV-sized rover there. Almost more difficult are the social aspects; the crew would be in near-isolation for around two years, with only each other and low-bandwidth links to Earth for company. Probably best to keep sharp objects safely stowed away.
And there's not actually a huge amount of curiosity which would be sated. We've sent four science labs to Mars, of increasing complexity. We've got hi-def photography, 3D scenes, panoramas; we've got chemical analysis of the rocks, satellite pics of geographic features and left miles of wheel grooves from exploration. In short, we've got everything other than a photo of a person standing on the planet.
If we are to use the death of the old generation of explorers to spur on a revival in the idea for this generation, let's also learn from their mistakes. Don't follow a paradigm which results in 0.0000003 per cent of the planet making it out of orbit; create a new one, which lets this massive achievement change the lives of many, rather than a lucky (or foolhardy) few.
In short, we need to build a space elevator.
The basic concept involves carbon nanotube ribbon stretching from sea level to 100,000 km up; well beyond the altitude of geosynchronous orbit (35,800 km). Earth’s gravity at the lower end of the ribbon, and a counterweight and outward centripetal acceleration at the high end of the ribbon, would keep the elevator’s “cable” taut and stationary over a single, fixed ground-based position. Robotic climbers would ascend the ribbon to various earth orbits and potentially enable the launch of spacecraft to destinations throughout the solar system.
There are a few problems to overcome, the main one being that we don't yet have any material which is strong enough to stop the cable from snapping due to the stress. But if you had told someone in 1954, the year Sputnik began development, that by 1969 there would be two people on the moon, they would likely have had the same objections.
And a space elevator frees us from the wasteful excesses of space flight. You would no longer have to strap yourself to the top of a bomb to get out of the earth's gravity well (the carbon emissions alone ought to give pause for thought – each launch of the space shuttle produces 28 tons of CO2 just from the engines, equivalent to driving a car for just under five years. And that's not counting all the rest of the operations involved in running the space centre). The cost of getting things into low-earth orbit would plummet. And if you did still want to go to Mars, it's a heck of a lot easier to do so in a rocket which is already in space by the time it sets off.
If we want to remember the pioneers of the 20th century, lets not do so with vanity projects of dying empires, but with exploration which really makes a difference. Let's build a space elevator.