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Saturday, 27 June 2015

Helium

French astronomer Pierre Jules César Janssen discovered helium on August 18, 1868, while analyzing the chromosphere of the sun during a total solar eclipse in Guntur, India.

Helium is the only element that was discovered in space before found on Earth. Because it was found when analyzing the Sun’s spectrum, its name which comes from the Greek word for Sun, Helios.

Helium is a finite resource on Earth and cannot be manufactured.

Although helium is the second most abundant element in the universe, most of it in the Earth's atmosphere bleeds off into space.

The US government has held a stockpile of 1 billion cubic meters of helium since 1925. This is due to post World War 1 fear that we may run out of helium in case of blimp warfare. The Federal Helium Program sells vast amounts of the gas to U.S. companies that use it in everything from party balloons to MRI machines.

Today, the US alone produces 75 percent of the world's helium. Nearly half of that total, or roughly 30 percent of the world's helium supply, comes from the U.S. Federal Helium Reserve. That reserve is held in a huge natural underground reservoir near Amarillo, Texas called the Bush Dome.

Helium discharge tune. By Alchemist-hp 

Because of their massive balloons during Thanksgiving parades, Macy's is the second biggest consumer of Helium in the world after the US Military.

Helium is one of lightest and least dense of all the elements. Its low density is what causes balloons filled with the gas to float, buoyed up by the denser surrounding air.

Helium is called a noble gas, because it does not regularly mix with other chemicals and form new compounds. It has the lowest boiling point of all the elements.  There are seven noble gases (the other six are Oganesson, Radon, Xenon, Krypton, Argon and Neon). Helium has the least density and it is the lightest of all the noble gases.

Because helium is easily compressed and non-toxic, it is used in specialized breathing mixtures of gases for very deep scuba diving, as a replacement for the nitrogen that makes up about 75 per cent of our air.

In 2013, Qatar started up the world's largest helium unit. The world suffered a shortage of helium four years later after Saudi Arabia closed its border with Qatar, as it accused the Gulf state of funding terrorism. Helium factories shut and global prices drifted upwards.

When liquid helium is cooled to just a few degrees below its boiling point of –452 degrees Fahrenheit (–269 degrees Celsius)  the lowest temperature possible, it becomes a superfluid with unusual properties: it flows against gravity and will start running up and over the lip of a glass container.
The liquid helium will also dribble through molecule-thin cracks and remain motionless when its container is spun due to its frictionless flow.

The largest single use of liquid helium is to cool the superconducting magnets in modern MRI scanners.

Liquefied helium

At the heart of the Sun 600 million tonnes of hydrogen are converted into helium every second.

Helium makes up around 45 percent of the mass of the sun.

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