A rare, colourless, odourless gas was discovered in 1898 by two British chemists, Sir William Ramsay and Morris W. Travers. They called it neon, which is the Greek word for "new". Neon is found not only in our atmosphere, but also in the gases trapped inside the Earth.
Because neon is a first-class conductor of electricity, possessing an amazing ability to generate light that can be seen at great distances, it is frequently used in airplane lights, lamps, and advertisements.
The bright red luminous signs we see outside stores and theaters are simply glass tubes in the form of letters or numbers, filled with neon gas. For blue neon signs, a few drops of mercury are added to the gas.
Neon lamps are built by removing all the air from the glass tubes and filling them with neon. When a lamp is turned on, an electric current is sent from one electrode at one end of the tube, passing through the gas, to a second electrode. This electric current makes the neon gas glow fiery red. Neon luminaires do not have filaments like those found in incandescent lamps, on the contrary, in neon lamps it is the gas that is illuminated.
The neon gas is obtained when the air becomes a liquid at high pressure and temperatures of about -200 ° C. The gas that leaves the liquid behind is the neon. Although neon is expensive to produce, it takes very little to create that bright light. Only one liter of neon gas is required to fill 60 to 90 meters of glass tubes.
Some pilots report having spotted neon beacons at a distance of 32 kilometers, when there is no other visible light!
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