The ballooning shortage of helium
Source: thestar.com
We usually think of it as the funny, lighter-than-air gas that makes balloons float and our voices squeak.
But those helium-filled party balloons are about to get a lot more expensive. Like uranium and oil, helium is running out. Created over billions of years, the earth’s supply could be gone in 25 to 30 years if we continue to waste it at its current rate, experts say.
The news has touched off a crisis in the science world, where the nontoxic, nonflammable substance holds the key to a myriad of scientific wonders, from modern medical diagnostics to the Large Hadron Collider.
Helium is a paradox: it’s everywhere and extremely rare at once. Next to hydrogen, it is the second-most abundant element in the universe, made inside stars. Yet on earth, it is hard to find: produced by the radioactive decay of rocks, most of it comes to us as a by-product of extracting natural gas, mostly in the American Southwest.
The world’s largest supply of helium is held in the U.S. National Helium Reserve in Amarillo, Tex., where it was stockpiled for use in military airships in the early twentieth century.
That store is being rapidly depleted, and scientists are worried. With its extremely low boiling point of 4.2 degrees above absolute zero (–269 degrees Celsius), liquid helium is the most important supercoolant used in science. NASA uses it to pressurize and clean rocket fuel tanks.
Its properties also make it valuable for cooling the magnets used in MRI scanners. A helium shortage would threaten millions needing MRI scans in hospitals worldwide.
Liquid helium is also key to manufacturing electronics, creating the controlled environments necessary to make semiconductors. It cools the superconducting magnets in CERN’s Large Hadron Collider near Geneva, which smashes protons together at nearly the speed of light.
Scientists have only begun to explore helium’s more exotic properties. When cooled down even further, it becomes a “superfluid”— a liquid without viscosity that can do seemingly impossible things, such as flow vertically up walls. Videos of liquid helium climbing up and over the sides of a container can be marveled at on YouTube.
Superfluid helium
Video from: YouTube.com
So what would be a more accurate price for a party balloon full of helium? Try $100, says Nobel laureate Robert Richardson, professor of physics at Cornell University.
At that price, the colourful display made by releasing hundreds of balloons would cost tens of thousands of dollars. It would be cheaper to pop hundreds of bottles of Veuve Cliquot.
A balloon’s journey into the sky illustrates why we’re losing helium so quickly. Once the balloon bursts — or once the gas escapes from a NASA rocket — the gas keeps on going up, up and away.
“Once it’s lost to the atmosphere, eventually it works its way into outer space and it’s gone forever,” says Darcy C. Burns, the associate manager of the Nuclear Magnetic Resonance facility, which also uses helium to cool its superconducting magnets, at the University of Toronto’s department of chemistry. Burns has become anxious about the future of the NMR since helium began becoming scarce.
“Liquid helium is used day-to-day in the sciences everywhere,” says Burns. “So it’s not just the helium itself that’s at stake, but our ability to do routine science all the way to novel discovery and innovation.”
So why are we letting a non-renewable element with unique physical properties literally float off into space?
Because the price of helium has been kept artificially low. A law passed in 1996 directed the reserve to sell off its helium by 2015, regardless of demand for it.
“(T)he consequence was that the market was swelled with cheap helium because its price was not determined by the market,” Richardson told The Independent.
An inquiry into the impending helium crisis convened by the U.S. National Research Council, part of the U.S. National Academy of Sciences, recommended that the American government stop selling off its helium reserves at fire-sale prices. Richardson has said the price of helium should rise twentyfold to fiftyfold to reflect its true value.
It is possible to recycle helium. It can be trapped in its gaseous state—for example as it boils off a magnet warmer than it — and run through a helium recovery system, which repressurizes it back into its cool, liquid form, ready to be used again.
The Nuclear Magnetic Resonance facility in the University of Toronto’s Department of Chemistry goes through 60 to 100 litres every week. But it doesn’t use a helium recovery system because, they say, it’s much cheaper to buy it.
While the earth may have a finite amount of the element, the moon has abundant quantities of helium-3, an isotope deposited by solar wind. But what would be the price of a balloon, filled with helium from the moon?
Article from: thestar.com
