How are neon lights made?

Neon lights are created by creating a vacuum, which is an area that is empty of air, in a glass tube and then pumping specific gases, such as neon, mercury and argon, back into that tube. According to Harvard University's Chandra X-Ray Observatory, the atoms of these gases collide and react with each other, releasing energy in the form of light.

Although neon lights are bright and seemingly modern, Arizona State University points out that the technology that makes these lights possible was actually developed in 1910. Neon itself is a gaseous element that creates a bright red-orange color when exposed to an electrical current. Other colors require different elements, such as a combination of argon and mercury, to make a blue neon light.