Thanks to The Observer for bringing this story to my attention.
Helium is a gas, and element number two in the periodic table. It’s the second commonest element in the universe, yet scarce on earth.
It takes a lot of cooling to turn helium into a liquid or solid: its boiling and freezing points are very low. These are the temperatures where super-conductivity comes into its own: hence its importance to science.
Earth has a limited amount of helium, and pockets of it are released as a by-product of oil and gas drilling. In the 1920s the USA thought helium would be important militarily given its use in airships. Accordingly the USA created a stockpile, running into billions of litres.
This changed in the 1990s. Having decided that helium was no longer significant, the USA has been selling off its helium, causing prices to fall. Helium became cheap – and we have seen the consequential rise – and rise – of the party balloon.
The essence of the story is that the stockpile has largely gone, prices are rising, and helium is beginning to become scarce – which could have a disruptive effect on scanners and other key devices.
By a stroke of luck, here’s a song that mentions helium. It’s at 1:19 if you want to skip the rest.