Rare white rainbow spotted in Florida, here's the explanation for this phenomenon

If you were at the wheel of your car on a Florida highway on Monday, January 1, then you may have been lucky enough to see a strange shape in the sky. No, it wasn't a UFO, but rather an atypical rainbow, devoid of colours. The Americans call it a 'fogbow'. In some other parts of the world, we know this phenomenon under the slightly less poetic and inspired name of the white rainbow.

The white rainbow

Picked up by several local media, the photograph taken by a motorist quickly went viral. While driving, the driver, who works for Melbourne's weather service, saw a gigantic arch in the distance. But unlike a 'normal' rainbow, this one had no colour. The arc in question was like a giant cloud in the shape of an arc, a mist arc, in a way!

On social networks, several internet users expressed their surprise. One Facebook user said she had seen the arch, and 'didn't know what it was'. Another user admitted that she had 'never seen or heard of a fog bow'. On a lighter note, one user lamented, 'There's no gold at the end of this one'.

Light passing through very small droplets

So what exactly is this all about? As everyone knows (well, almost everyone), a rainbow occurs when sunlight is refracted through drops of water, the white light then breaks down into seven colours. This is why rainbows always have their backs to the Sun.

The principle is similar for the white rainbow, except that in this case the light passes through water drops smaller than 0.05 mm, according to Newsweek, the average size of a raindrop varies between 0.5 mm and 2 mm. The result is, the decomposition of colours is weaker, and we can thus observe these famous whitish arcs!

This article was translated from Gentside FR.

Sources used:

-Newsweek: Rare Ghostly 'Fogbow' Appears Over Florida