The war in Iran is impacting Earth's supply of helium

Helium is the second most abundant element in the universe. But here on Earth, there's a limited supply.

GEOFF BRUMFIEL, BYLINE: It literally just leaves the Earth, and it escapes the atmosphere. It's light enough. It goes off into space. And so any helium that's in our atmosphere will eventually work its way out of the atmosphere and into space.

RASCOE: That's NPR science correspondent Geoff Brumfiel talking to NPR's Short Wave podcast. Helium is super light, making it the ideal gas for pumping up birthday balloons and blimps. But it has another useful attribute. It's the coldest substance on Earth. In its liquid form, helium is 4.2 Kelvin. That's -452 degrees Fahrenheit. So liquid helium has become the go-to gas for cooling things down, ranging from supercomputers to rockets.

BRUMFIEL: Helium was actually used in every stage of the Apollo program, from the giant Saturn V rocket to the lunar lander. When it took off, it used helium to make its engine run.

RASCOE: All that helium comes from deep underground.

BRUMFIEL: Helium on Earth is created by the natural radioactive decay of heavier elements like uranium and thorium. When one of these atoms splits apart, boop - out comes an atom of helium. And as it accumulates inside the Earth, it kind of filters up because it likes to float, and then it gets trapped in these pockets in the crust.

RASCOE: Helium is captured as a byproduct of drilling for natural gas, but there are only a few places that currently produce it. The world's top producer is the U.S., but No. 2 is Qatar, which makes about one-third of the world's supply. So when there's a crisis in the Gulf region, it's not just the world's oil markets that take a hit. Recently, helium prices have soared as much as 50% due to the Iran war. And the supply chain is tight. Helium is shipped in its liquid form and has to be used shortly after being mined. Otherwise, it evaporates. Experts say it could take weeks or months to restore helium deliveries to normal, even after the conflict ends.

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