Rainbow is one of the most amazing natural phenomena. What is a rainbow? How does she appear? These questions have interested people at all times. Even Aristotle tried to unravel its mystery. There are many beliefs and legends associated with it (the road to the next world, the connection between heaven and earth, a symbol of abundance, etc.). Some peoples believed that whoever passed under the rainbow would change their gender.
Her beauty strikes and delights. Looking at this colorful "magic bridge", I want to believe in miracles. The appearance of a rainbow in the sky notifies that the bad weather is over and a clear sunny time has come.
When does a rainbow happen? It can be observed during rain or after a downpour. But for its occurrence, lightning and thunder are not enough. It appears only if the sun breaks through the clouds. Certain conditions are necessary for it to be noticed. It is necessary to be between the rain (it should be in front) and the sun (it should be behind). Your eyes, the center of the rainbow and the sun must be on the same line, otherwise you will not see this magical bridge!
Surely many have noticed what happens when a ray of white light falls on a soapybubble or on the edge of a beveled mirror. It is divided into various colors (green, blue, red, yellow, purple, etc.). The object that breaks the beam into its component colors is called a prism. And the resulting multi-colored line - the spectrum.
So what is a rainbow? This is the curved spectrum, the colored band that results from the splitting of a beam of light as it passes through raindrops (they are a prism in this case).
The colors of the solar spectrum are arranged in a certain order. On the one hand - red, then orange, next - yellow, green, blue, blue, purple. The rainbow is clearly visible as long as the raindrops fall evenly and frequently. The more often, the brighter it is. Thus, three processes occur simultaneously in a raindrop: refraction, reflection and decomposition of light.
Where to see a rainbow? At fountains, waterfalls, against the background of drops sprayed by a watering machine, etc. Its location in the sky depends on the position of the sun. You can admire the entire rainbow circle if you are high in the sky. The higher the sun rises above the horizon, the smaller the colored semicircle becomes.
The first attempt to explain what a rainbow is was made in 1611 by Antonio Dominis. His explanation was different from the biblical one, so he was sentenced to death. In 1637, Descartes gave a scientific explanation for this phenomenon based on the refraction and reflection of sunlight. At that time, they did not yet know about the decomposition of the beam into a spectrum, that is, dispersion. Therefore, Descartes' rainbow turned out to be white. After 30 years, Newton "colored" it, supplementing his colleague's theory with explanations of the refraction of colored rays in raindrops. Despite the fact that the theory is more than 300 years old, it correctly formulates what a rainbow is, its main features (arrangement of colors, position of arcs, angular parameters).
It's amazing how familiar to us light and water create together a completely new, unimaginable beauty, a work of art given to us by nature. The rainbow always causes a surge of emotions and remains in memory for a long time.
