A space elevator would be a fitting tribute to Neil Armstrong
Let's focus on projects that would change the world substantively, not symbolically.
On 25 August, Neil Armstrong, the first man on the moon, died. He was 82. Armstrong’s death made apparent the failure to build on his generation’s legacy. Just 12 men (and no women) have set foot on an extraterrestrial surface. Today, eight remain, and none born after 1935. Space travel, it seems, is an old man’s game.
Coming so soon after the success of the Mars Science Laboratory mission – in which Nasa has landed a nuclear-powered, laser-armed, one-tonne rover on the red planet – his death has focused attention on the only other planet in the solar system on which human beings could conceivably walk. (Mercury and Venus would kill you in seconds; the gas giants are, well, gas; and Pluto is so cold, oxygen freezes.)
But no matter how impressive the trip to the moon was, it was as much a product of cold-war showmanship as the urge for exploration. The US went to shove a big Stars and Stripes in the face of the Russians. That doesn’t lessen the achievement, but it does place a question mark over the idea of repeating it.
We could put people on Mars. The technical aspects are tricky, though not much more so than putting an SUV-sized rover there. But how much would it contribute to our existing knowledge? We have taken HD photography, performed chemical analysis of rocks and left miles of wheel grooves from exploration. In short, we’ve got everything other than a photo of a person waving in front of Olympus Mons.
If Armstrong’s death does spur a revival in space exploration, then let’s learn from his generation. Let’s not follow a paradigm that results in 0.0000003 per cent of the planet making it out of orbit but create a new one that focuses effort on projects that will change the world substantively, rather than symbolically.
The International Space Elevator Consortium has one such suggestion and has been putting money towards it for four years. If you have ever played swing-ball, you understand the basic principle of a space elevator. Attach a cable from the earth’s equator to an asteroid, use centrifugal force to keep the whole system taut, and then send self-powered climbers up and down the structure. The end result is something that looks a lot like a tower into space but in practice is more like an Indian rope trick: the elevator is pulled up from space, rather than supported from the ground. Once it is built, the energy cost of lifting one kilogram into space drops from about $20,000 for conventional rockets to about $200.
There are a few problems to overcome. For example, we don’t have any material strong enough to stop the cable from snapping. But advantages in carbon nanotube technology look promising; and in 1949, we didn’t even have the means to get into orbit, let alone to the moon.
We still think of space travel as futuristic. But if we do want to carry on pushing the boundaries of human endeavour, we need better ways to do it than strapping ourselves to the top of a 2.8 megatonne bomb and pointing it towards Mars.