A riddle: What’s the thing that there’s more of than nearly anything else, but which we haven’t got enough of? Would you like some clues? It’s used in dating. No, not Match.com and Tinder, carbon dating, and stuff. Working out how old rocks are. No, it’s not carbon. Too much of that, remember – at least in the atmosphere. It’s used in rockets. No, not the ones that go whoosh on November 5th – though more about celebration later – the ones that they send Tim Hunt up to the space station on. Not Tim Hunt, Tim Peake. Tim Hunt got sent to Japan. No, it’s not Oxygen, no one’s suggesting that there’s not enough of that to go around (as far as I know, which may not be very. Check the title of this blog. I don’t have a team of fact-checkers). It’s used in MRI scanners and the Large Hadron Collider. Come on, you must be getting close now, there can’t be many things that get caught by all of these. What do you mean you don’t understand how Magnetic Resonance Imaging works. What do you mean until the last sentence you didn’t know that’s what it stood for?
The answer, my friends, is blowing in the wind – which is partly the problem. It’s helium. The second most abundant element in the universe after hydrogen. Almost all of the universe is either hydrogen or helium, and even helium is a waste product of all the hydrogen which is getting burnt up in the all the stars, of which our sun is one. I say ‘burnt up’ because in everyday sense, people think of the stars burning, but of course they don’t. I suppose it might not be widely known that stars are basically hydrogen bomb explosions that have been going on for billions of years, because there’s so much hydrogen in them to use up.
What’s that? You don’t know much about hydrogen either? Or hydrogen bombs? Okay, I’ll give you my Brian Cox summary, though I have considerably less hair, and the band I was in never had a number one hit. Or a hit, come to that, though Disco Urinal was popular with a fortunate few who heard its five performances.
Here’s nuclear fission. When you break a big atom into two smaller atoms, you get a bit of extra energy left over. If you do it with enough big atoms at the same time, you can demolish Hiroshima. Or power Fukushima. It all depends on how much you control it. Now here’s the weird bit – if you have really small atoms – hydrogen is as small as they come, having just a proton in the middle and an electron whizzing around it – and bash them together, instead of breaking them apart, you get a bit of extra energy left over. This is called fusion power.
Now, there are all kinds of reasons why we’d love to be able to build fusion reactors, but we can’t. Oh great, you’re going to say, we put all the work into the technology to build a hydrogen bomb, but we can’t be bothered to put in the leg work for peaceful uses like power, which would probably save the planet. The thing is, fusion of hydrogen atoms can only take place at fantastically high energy levels. The bomb gets round this by starting off with an atomic bomb – a fission explosion – and then fires the fusion explosion off that. But you can imagine the outcry if we had to keep exploding atom bombs to power the homes of Surrey and Hull, given how grumpy people seem to get about fracking. Any kind of fusion power, so far as we currently know, needs a huge amount of power put in before you get anything extra out.
But you’re right, it probably would save the planet. If we could crack fusion power, we could forget wind, solar, oil, gas, petrol and fission. What, you say, get rid of those lovely wind turbines? Make redundant those fields of rectangular black panels? Lose those evocative ‘nodding donkeys’ and those romantic North Sea oil rigs? What about the danger of meltdown, and all the terribly dangerous and toxic waste products? The danger of meltdown, I don’t know about, but the thing about hydrogen fusion is that it’s clean. The main by-product of hydrogen fusion is, as I hinted earlier, helium. No krypton-92 or barium 141 to get rid of by burying underground in vaults that will split open and poison future generations. No, helium. Helium. Which is where I began.
The thing about helium is that it’s light. Oh yes, there’s going to be a scientist along in a moment to tell me that I should say ‘less dense’, but only someone especially dense would think that I wasn’t talking about the weight of some particular volume of helium compared to other things. Fill a balloon with air and it will bob up and down a bit, but hit the floor. Fill it with helium, and as you know, your children are charmed by its simple magic until they let go of it and you have to buy them another one. Or until the helium leaks out, and the balloons go wrinkly and gradually hit the ground. Just like their parents will. (Too dark? I’ll take that bit out then).
Which is another part of our problem. There’s only so much helium on earth. There’s more of it than we could ever hope to use in the photosphere of the sun, but piping it back home is going to present more than a few engineering difficulties. We’re entirely dependent on all the stuff that’s been locked up inside the earth’s crust, and which we harvest alongside natural gas (actually methane, one of those greenhouse gases, but which cows and people also produce. Sorry). The problem with the stuff that’s on earth is that once it’s loose in the atmosphere – like the stuff that leaks out of the kids’ balloons, it just keeps heading up. And up and up and up. Through all the oxygen and nitrogen and yes, that carbon dioxide and the other greenhouse gases, the ozone and whatever until presumably it forms a huge, inert and pointless sphere around the earth, still too far away to be of any use at all.
So eventually, no more helium to make the balloon strings go stiff. More to the point, none to supercool the innards of MRI scanners so they can scan your innards when you need it. None to pressurise the fuel of rockets to get Tim McInnerny into space. None for deep-sea divers to breathe, as they currently do, when they are working on those North sea oil rigs you find so romantic. (Yes, it makes their voices squeaky. They live in little pressurised caravans at the surface that have a special intercom that translates their squeakiness back to audible frequencies. This is true.)
In 2012 it was being reported that the US, which produces more than 75% of the world’s helium, was predicting a gradual reduction of helium production from its Amarillo reserve until it would cease production by 2020 at the latest, and the hope was that other sources would be found. People were calling for the use of helium in party balloons to be banned as the least important of the many uses of this inert element. What were they thinking? Especially since we’re today told that we’re about to start manufacturing airships full of helium, to enter service in 2018. What difference will our little bit make?
Fear not. It is now believed that there are vast new reserves of the element waiting to be mined in – you guessed it – the US. By such a simple process as comparing the ratios of helium with neon in the Hugoton Panhandle gas field, Diveena Danabalan and her team have established that (probably) there will be more helium available than you can shake a starch-stiffened balloon string at.
 Sort of. Better than the Sphynx’s anyway.