FIFTY years ago yesterday, Apollo 11 was launched, separated from the Saturn V rocket that propelled it into its flight azimuth, and headed for the Moon. Five and a half days later, Neil Armstrong stepped on to the surface.

It must have felt (I’m told that, technically, I watched it, but can’t remember it) like the beginning of a new era: Stanley Kubrick’s 2001: A Space Odyssey the previous year had promised lunar bases and Pan Am flights to them by the new century; Star Trek three years earlier declared space, and the eradication of the grammatical infinitive, “the final frontier”. David Bowie’s Major Tom was, like Armstrong, Buzz Aldrin and Michael Collins, sitting in a tin can, far above the world, waiting (the BBC refused to play the record until the astronauts returned safely). A lot had happened since the Space Race began in 1955, when the wild frontier was still Fess Parker’s theme tune for Davy Crockett.

Instead it was, pretty well, the beginning of the end. Space programmes continued; Europe (which, like Eurovision, initially included Australia, and now includes Canada), China, Japan and India, as well as the USA and Russia, have them. There’s the International Space Station, countless unmanned satellites – upon which each of us depends daily – and renewed talk of going to Mars.

But for the most part, space is yesterday’s potatoes, rather than the potatoes of tomorrow planted by some Matt Damon-like astronaut trying to colonise another world. Concern about the future of humanity in the next 50 or 100 years is almost entirely focused on eradicating drinking straws, plastic bags and the use of fossil fuels, rather than flying cars around a Buckminster Fuller-domed city on Proxima Centauri B, while got up in some outfit reminiscent of Milo O’Shea or Jane Fonda in Barbarella.

That’s a shame, I think. Worse, an error. In the grand scheme of things, getting a few people into space doesn’t look like a priority compared with avoiding nuclear annihilation, climate meltdown or trashing terrestrial ecostructures. And our record so far – a dozen white American men briefly visiting the nearest celestial body – is the smallest of steps for mankind.

Even if we try to fix it, though, there’s a problem with “the only world we have”, as environmentalists like to put it. Leave aside the fact that extreme eco-alarmists have all been wrong in their predictions of the past 50 years about where we would be now. In 2009, for example, Prince Charles told us we had 100 months to save the world. Two years after we all presumably died, he popped up again the other day to give us 18 months, as if extinction were operating on some Brexit-style series of interminable extensions.

The climate and ecology Jeremiahs may well, nonetheless, be right about some things. And even if they’re wrong about the nature of the impending apocalypse, or whether it’s caused by human behaviour, over-consumption, pollution or something else that we might control or amend, it is a mathematical certainty and a scientific fact that the Earth is doomed.

At the very least, the planet will fall into the Sun in 7.5 billion years. But plant life will be extinguished in a mere 600 million years, even if nothing happens before then. That’s very unlikely; in the past 540 million years, there have been at least five mass extinction events. These all happened before we came up with single-use plastics, so even if we can avoid killing ourselves, something else will certainly do it.

The most likely candidates are a massive asteroid collision (if the Tunguska event of 1908 had been Europe or America rather than Siberia, that would have happened already), or some natural catastrophe, probably volcanic, tectonic, oceanic or geomagnetic. The average interval between the eruption of any active supervolcano is 100,000 years; the last was about 30,000 years ago in New Zealand, but there are about 50 on the planet; Yellowstone National Park, which is one, is about 50,000 years overdue to blow its top on the basis of its previous behaviour.

In other words, the end is nigh(ish). Unless, that is, we pay more attention to Elon Musk than Greta Thunberg: I grant you, not an immediately appealing prospect. The rationale is this: even if Miss Thunberg’s right, and we do everything she suggests, we’re doomed, because sooner or later something over which we have no control will wipe humanity out. Whereas, if enough of us get off the Earth first, as Musk suggests, there’s the possibility that humanity’s descendants will survive.

To do it, they’ll probably have to become post-human in some way. But then, that’s evolution. Space colonisation, perhaps with attendant genetic changes, or digital upload of consciousness, or some as-yet unimagined development, is currently the stuff of science fiction. A century ago, so were nuclear power, the computer, antibiotics, talking pictures, the ballpoint pen, frozen food, the jet engine, the contraceptive pill, transistors, the personal stereo, GM crops, contact lenses, mobile phones, DNA sequencing, suntan lotion and Velcro. And the idea that Man could walk on the Moon.

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