Neon is a colorless noble gas at room temperature with about two-thirds the density of air. Like the other noble gases, neon is inert, which means that it is not chemically active.
Both the melting and boiling points of neon are below minus 400 degrees Fahrenheit, so it isn't often seen as a solid or liquid. The bright colors used in neon lights and signs are caused by the red color emitted by the gas when it is charged with electricity and mixed with other compounds to give a wide array of colors. Although neon is one of the most abundant chemicals in the universe, it is rare on Earth.