The Glowing Science: How Neon Signs Illuminate Our World

-Karthik Gurumurthy

Ever wonder how those cool neon signs actually work? It’s pretty fascinating science!

Neon itself is just a colorless, odorless gas that was discovered back in 1898 by two British scientists, Sir William Ramsay and Morris W. Travers. They named it after the Greek word for “new.” Perfect timing, because around that same period, physicists were playing around with electricity in evacuated glass tubes.

The real breakthrough came in 1910 when a guy named Georges Claude filled a tube with purified neon gas and zapped it with high voltage at both ends. What happened? The tube lit up with this amazing deep red glow! But here’s the thing – for this to work properly, the neon has to be super pure, with no other gases mixed in. They use charcoal to pull out all the impurities.

The process involves cooling the gas to incredibly cold temperatures (between -180 to -190 degrees Celsius) which makes any impurities stick to the tube walls so they can be removed.

People quickly realized the commercial potential, and by the early 20th century, neon lighting became a big deal. But they didn’t stop with just neon! Scientists started experimenting with other gases too. Mercury vapor, for instance, produces a blue light.

Those white fluorescent lights that were developed in the 1930s? They’re actually mercury vapor tubes with a special trick – the inside of the tube is coated with a material that fluoresces white when exposed to the radiation from the mercury.

It’s basically electricity exciting gas atoms until they glow – pretty much like tiny lightning in a tube that we’ve tamed for decorative purposes!