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Hello, I'm Justin Rowlatt. Welcome to Business Daily and the second part of our series looking at the world from the

perspective of the chemical elements today we are looking at helium the second most abundant

element in the universe but very rare on earth helium is unique is helium when's gone, it's lost to us forever.

In liquid form, it is the coldest element, and that makes it very useful.

So much so that the US has its own National Reserve.

Outside the fence, there's not much more than electricity pylons and scrub and brown earth. But inside is the heart of the

world's largest reserves of helium. So why do we waste helium in children's party balloons? That's

all in Business Daily from the BBC. So it's time to forget about trade flows and financial markets, company results and

economic indicators, because we're taking a completely different approach to the world

economy. We're looking at it chemical element by chemical element with surprising results.

Last week, we looked at phosphorus, a highly reactive solid.

Today it's an inert gas, helium, two very different elements, but reserves of both are finite

and could one day run out. So where does helium come from? Here's chemistry professor Andrea

Seller of University College London to explain.

Helium is really kind of interesting because it wasn't discovered on Earth.

It was first observed on the Sun when astronomers suddenly realized that there was light coming from the Sun,

which must be coming from an element that they had never seen before. They had matched up

all the other components of the solar spectrum. And there were a few lines that didn't fit. And so

two scientists concluded that this must be a special element associated with the sun. And so

they called it helium, after the Greek word helios for the sun. This was at the

end of the 1880s, and the question was, where might it be on earth? And you've come to the right

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