As we progress through the 2020s, life continues to blend with virtual reality. So much so that sometimes you can see something IRL and believe with the utmost conviction that it must be a computer generated visual effectOpens in a new tab. The YouTube channel The Slow Mo Guys gives us our latest taste of real-life simulation with a rainbow fire tornado. And it looks like a trippy digital hologram.
The Slow Mo GuysOpens in a new tab recently posted their rainbow fire tornado, which dovetails two previous pyrotechnic projects. Including a non-rainbow fire tornadoOpens in a new tab and an array of slow-mo multi-colored flames.
As Slow Mo Guys host Gavin Free shows, he’s able to create the rainbow fire tornado thanks to 14 fans and an assortment of different flammable liquids. Free shows how he uses four different flammable liquids to make the rainbow tornado. He uses strontium chloride for red flames; boric acid for green flames; copper chloride for blue flames, and calcium chloride for orange flames.

Incredibly, it appears that Free simply dumps the four different liquids into a bucket and then uses a torch to light them on fire. Each chemical liquid burns a different color because it has a different metal salt. As the metal salts heat, their atoms move to an excited (or unstable) state. When they return to their original (stable) state, they release excess energy in the form of light of a certain wavelength. (We perceive different wavelengths of light in the visual spectrumOpens in a new tab as different colors.)
While the science is cool, the fiery rainbow tornado itself looks genuinely unreal. Downright magical. It’s hard to say why exactly, although Free notes at one point that the rainbow’s reminiscent of a (feasting) black holeOpens in a new tab. We can also see it as the Eye of Sauron from The Lord of the RingsOpens in a new tab.