One hundred sixty years ago, scientists invented the spectroscope, which breaks light into its spectrum of colors.

They soon discovered that some elements, when heated, produce a signature light color. Hydrogen, for instance, makes orange.

When they pointed the spectroscope at the sun, they saw lots of orange—and some yellow, which didn’t match any element on Earth.

They named this alien element helium, after the Greek sun god Helios.

For decades, many doubted its existence. Until a scientist aimed the spectroscope at lava and saw the yellow again. Helium had been found on Earth.

Further study revealed that helium was being produced by the decay of uranium and trapped underground in reservoirs. It also revealed that it’s a very special element.

Helium is so light that Earth’s gravity can’t hold it. When released at the surface, it rises through the atmosphere into space.

It’s also inert: helium won’t bond with other elements, meaning it’s nontoxic and nonflammable. That makes it useful to create sterile, nonoxidizing environments for medical procedures, clean rooms, and welding.

Helium also enters its liquid state colder than any other element. Liquid helium is therefore used to cool superconductor magnets, and in MRI machines and nuclear colliders.

So next time you see helium balloons at a party, or inhale it to sing happy birthday in a chipmunk voice, remember that helium itself is an element worth celebrating.