Sunset? Not quite.

Look at this photo:

Estas fotos (a anterior e a do final do post) foram tiradas por mim durante o pôr-do-sol do dia de hoje (bem, ontem, visto que já passada da meia noite). Nunca tinha visto um arco-íris completo à volta do sol com dois pontos mais brilhantes de cada lado do sol... Parecia que o céu tinha três sóis, beautiful indeed.

Fiquei curiosa e fui pesquisar sobre o assunto e foi isto que descobri:

Este fenómeno é bastante comum e dá pelo nome de Parélio. "(...) É um fenómeno ótico atmosférico que consiste em um ponto brilhante à esquerda e/ou à direita do Sol. (...)

O parélio é um membro da família de halos, causado pela refração da luz solar por cristais de gelo na atmosfera. (...) Podem ser vistos em qualquer lugar do mundo durante qualquer estação, mas nem sempre são claramente visíveis ou brilhantes. Os parélios são melhor vistos e mais visíveis quando o Sol está perto do horizonte.

É um fenómeno ótico atmosférico associado principalmente com a reflexão e refração da luz solar por pequenos cristais de gelo provenientes de nuvens cirrus ou cirrostratus. (...)"

- Wikipédia

"(...) What is a snow rainbow?

A rainbow can only occur if there are raindrops in the air - as they are caused by the refraction and dispersion of the sun's light by rain or other water droplets in the atmosphere.

However, the exact same physics that happens in raindrops also happens in snow and ice crystals to create a snow rainbow or snow bow.

This can also create colour patterns similar to rainbows. (...) Snow can cause a sun dog called a parhelion. (...)

A parhelion is an atmospheric optical phenomenon that is the result of light passing through ice crystals to cause two bright spots on either side of the sun.

This creates the illusion there are three suns in the sky, or a bright orb surrounding the sun. (...)"

- Express UK

"(...) A sundog (...) is a bright, rainbow-colored patch of light that occurs on either side of the sun when it is low on the horizon — just after sunrise or before sunset, for instance. Sometimes, a pair of sundogs will appear — one on the sun's left, and another on the sun's right.

Why Are Sundogs Called Sundogs? It isn't exactly clear where the term "sundog" originated, but the fact that these optical events "sit" beside the sun — like a loyal dog attends its owner — likely has something to do with it. Because sundogs appear as bright-yet-miniature suns in the sky, they are also sometimes called "mock" or "phantom" suns. Their scientific name is "parhelion" (...)

Part of the Halo Family: Sundogs form when sunlight is refracted (bent) by ice crystals that are suspended in the atmosphere. This makes the phenomenon related to atmospheric halos, which are white and colored rings in the sky that form by the same process. 

The shape and orientation of the ice crystals through which the light passes determines the type of halo you'll see. Only ice crystals that are flat and hexagonal—known as plates—can create halos. If the majority of these plate-shaped ice crystals are positioned with their flat sides horizontal to the ground, you will see a sundog. If the crystals are positioned at a mix of angles, your eyes will see a circular halo without the distinct "dogs."

Sundog Formation: Sundogs can and do occur worldwide and during all seasons, but they are most common during winter months when ice crystals are more abundant. All that's needed for a sundog to form are either cirrus clouds or cirrostratus clouds; only these clouds are cold enough to be made of the necessary plate-shaped ice crystals. The size of the sundog will be determined by the size of the crystals. (...)

Sundogs and Secondary Rainbows: Sundogs may look like bite-sized rainbows, but inspect one closer and you'll notice that its color scheme is actually reversed. Primary rainbows are red on the outside and violet on the inside, while sundogs are red on the side nearest the sun, with colors grading through orange to blue as you travel away from it. In a double rainbow, the colors of the secondary bow are arranged in this same way.

Sundogs are like secondary rainbows in another way too: Their colors are fainter than those of a primary bow. How visible or whitewashed a sundog's colors are depends on how much the ice crystals wobble as they float in the air. The more wobble, the more vibrant the sundog's colors. 

A Sign of Foul Weather: Despite their beauty, sundogs are indicative of foul weather, just like their halo cousins. Since the clouds that cause them (cirrus and cirrostratus) can signify an approaching weather system, sundogs themselves often indicate that rain will fall within the next 24 hours."

- ThoughtCo.

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