A Double Rainbow Shines Over Alicante After an Afternoon of Showers

On Monday afternoon, the city of Alicante experienced several showers. Many residents were caught off guard as they left work, only to find themselves in the midst of the phenomenon, getting soaked.

Others were at home, sheltered. It was there that they were also struck by another spectacle: a double rainbow that appeared over the city of Alicante following the downpours.

The raindrops gave way to a rainbow visible from all corners of the provincial capital. In some areas, it was more intense, allowing the phenomenon to be appreciated twice over the Alicante sky.

This phenomenon has occurred in the city before. To understand why the rainbow duplicates, one must turn to physics, which explains the various orders and factors involved.

To begin explaining, it is important to note why a rainbow forms. This phenomenon occurs due to reflection and refraction, when light passes through water droplets that act as transparent mediums.

It is an effect that causes a change in the direction of the sun's rays, displaying a spectrum of colours that vary in brightness and clarity, revealing this rainbow to the people of Alicante. This is where the first order comes into play.

The double rainbow is due to a second order in the reflection of the sun's rays. Once they reflect directly on the surface of the droplets, their effects continue, and the light also transmits through the droplets. This is what forms a second rainbow as the light bounces inside them.

This second rainbow loses intensity compared to the first, and its colours appear in reverse order. Carlos Pastor, a professor of Applied Physics at UMH, explains that the density of the phenomenon "decreases with each order," which is why the first rainbow is more visible.

Another curiosity of this double rainbow is that the hue of the sky itself—highlighted by the number of clouds—shows greater darkness between the two phenomena (there can also be three with a new order). This is known as the 'Alexander's band,' which lies between the first and second order.