Helium

When you think about helium, you might immediately think about balloons. But those joyful party decorations weren’t around when scientists and astronomers first observed the element during a solar eclipse in 1868. Pierre Janssen, a French astronomer observing the eclipse from India, wasn’t the only one to notice a yellow line around the sun, but he was the one to formally record and confirm the new spectrum line. Around the globe, Joseph Norman Lockyer observed the new gas while viewing the sun through London’s smog. Lockyer named the element helium after the Greek word for the sun, helios. Although their observations were a few months apart, Janssen’s and Lockyer’s papers arrived at the French Academy of Sciences on the same day, and they share credit for the discovery—but many of their scientific peers were skeptical that they’d actually discovered anything.

In 1882, Italian physicist Luigi Palmieri detected helium while analyzing material from a volcanic eruption, and that research laid the foundation for Scottish chemist William Ramsay to successfully isolate the gas in 1895 after finding it within a piece of uranium ore. Later that year, Swedish chemists Per Teodor Cleve and Abraham Langlet collected enough helium to accurately determine its atomic weight. Ramsay sent a sample to Lockyer, who celebrated the confirmation. Research doesn’t happen in isolation and helium’s discovery was certainly a team effort!

Helium is a colorless, odorless, non-toxic, gas. It is the first in the noble gas group in the periodic table, and like the other noble gases, it is very stable and doesn’t react with other elements. Helium has the lowest boiling point of any element—close to absolute zero—and it’s the only element that can’t be solidified or frozen at normal atmospheric pressure.

Beyond buoyant party décor, helium has many uses.

Want to learn a trade? Helium is used in arc welding for construction, vehicle assembly, and aerospace manufacturing.

Curious about energy? Helium helps cool nuclear reactors.

Injured your knee? Magnetic resonance imaging (MRI) machines can’t work without helium and allow millions of patients each year to avoid unnecessary surgery.

Going scuba diving in Hawaii? A mixture of helium and oxygen is used as an artificial atmosphere for divers and others working under pressure.

Reading this on a cell phone or laptop? Helium is used in the production of computer chips, fiber optics, and semiconductors that support modern communications.

As the smallest and lightest noble gas, helium doesn’t make friends—um, compounds—easily. It's happy with just its two electrons and isn’t interested in accepting extra electrons or joining other elements. That means it has no stable compounds under normal conditions.

If forced, helium can form weak bonds with other helium atoms under incredibly low temperatures, but because it is so stable on its own, a single atom is considered a helium molecule.

In the 21st century, scientists have been able to predict some stable helium compounds, which might exist within gas giant planets. To bond with other elements, helium must be subjected to high pressure. One of the most well-studied potential helium compounds pairs it with two sodium atoms, resulting in a unique crystal structure.

Helium is the second-most abundant element in the universe and exists in our air, but we can’t isolate and harvest the element. Because it is rare on Earth, we collect it through other means, including as a byproduct of mining natural gas.

In 1925, the United States created the National Helium Reserve, and by 1995, the reserve held more than 1 billion cubic meters of the gas. At that point, demand for helium had decreased too much to justify the storage costs, so the government phased out the reserve and began selling off the stored gas. By 2013, high-tech applications renewed demand for helium, and the Bureau of Land Management took over national helium storage.

Today, helium continues to come from wells in the American Great Plains; however, the small Middle Eastern country of Qatar supplies the most helium in the world.