Optical phenomena: examples. Light, a mirage, a northern light, a rainbow

Man is a great master of building castles on the sand. However, practice shows that he is far from Mother Nature. The master of God is capable of such a deception of our senses that the spirit captures! But no matter how magical optical phenomena appear, the examples of which we will consider, they are not phantasmagoria, but the result of the flow of physical processes. In the inhomogeneous atmosphere of the Earth, the rays of light warp, causing a host of illusions. But can you imagine a world without dreams and visions? He would be so gray ...

Light and color

Speaking about optical phenomena, the light and forms of which are observed by more than one generation of people, we emphasize that colors appear in the atmosphere due to the fact that white light during the interaction with materials in the atmosphere is broken up into component parts (spectrum). This interaction is realized by means of one of three basic forms: reflection, refraction (refraction) and diffraction.

If we are talking about the spectrum, think about how to teach your child to remember the sets of colored bands that result from the passage of a light beam through a refractive medium. A simple phrase can help: "Every (red) hunter (orange) wishes (yellow) to know (green), where (blue) sits (blue) pheasant (purple)".

Reflection of light is the emergence of secondary waves propagating from the boundary of two media back to the first medium. Refraction - refraction of rays on the boundary of two media. Diffraction - bending light particles, droplets of liquid, and other materials present in the atmosphere. All this is the cause of the "optical illusion of sight" that is flourishing in the universe. There are many examples: from the blue color of the sky, the mirages and the rainbow to false suns and solar pillars.

Internal Reflection

Optical phenomena in physics are an important section worthy of in-depth study. So let's continue. Reflection occurs when light rays fall on a smooth surface and return at an angle equal to the incoming one. This phenomenon explains the origin of color: some white parts are more easily absorbed and reflected than others. For example, an object that appears to be green appears to be so because it absorbs all wavelengths of white light, except for green, which is reflected.

One form - internal reflection - is often present in explaining optical phenomena. Light enters a transparent physical body (material), for example a drop of water, through the outer surface and glows already from the inside. Then, the second time - from the material. The color of the rainbow can be partially explained in terms of internal reflection.

Rainbow-arc

Rainbow is an optical phenomenon that happens when sunlight and rain are combined in a specific way. The rays of sunlight are divided into colors that we see in the rainbow when they enter the raindrops. This happens when the beam falls on the "rain" directed to the Earth at a certain angle, the colors are separated (white light decomposes into the spectrum), and we see a bright, festive rainbow resembling a giant semicircular bridge.

It seems that the diversity of curved bands hangs right over your head. The radiating source will always be behind us: to see at once a clear sun and a beauty-rainbow is impossible (except if using a mirror for this purpose). The phenomenon is not alien to the Moon. When the moonlit night is bright, you can see a rainbow "fan" and close to Selena.

When almost nothing is visible around, the most receptive to the light photoreceptors of the human eye - "sticks" work. They are sensitive to the emerald green part of the spectrum, other colors "do not see". As a result, the rainbow looks whitish. When the lighting amplifies, connect "cone", thanks to these nerve endings, the arc looks more colorful.

Mirage

From the Earth, we observe only a part of the circle of the primary rainbow. The light undergoes one reflection. In the mountains you can see a round rainbow. Do you know that "beauties" are two or even three? The rainbow, which shot up above the rainbow, is less bright and "inverted" (after all, it is the reflection of the first). The third happens where the air is crystal clear and transparent (for example, in the mountains). This is about the usual spectacle.

Mirage is an optical phenomenon that can not be called ordinary. In Russia it is relatively rare. Each time, when uttering a magic word, we remember the legend of the ghost ship "Flying Dutchman". According to the legends, for the crimes of the captain, he will plow the ocean expanses until the second coming.

And here is another "Dutchman". The "Ripals" cruiser became volatile, sunk in December 1941 off the coast of Ceylon. He saw "very close" the crew of the British ship "Vendor", located in the Maldive Islands. In fact, the ships shared 900 kilometers!

Fata Morgana

"Flying Dutchman" and others - optical phenomena, examples from the cohort of stunning mirages "fata morgana" (named after the heroine of the British epic). An unusual optical phenomenon is a combination of several forms. In the sky, a complex, rapidly changing image is formed. Looking at the types of what is far beyond the horizon, it seems, you can go crazy, so much they are "tangible."

Miracles caused by atmospheric conditions can be confusing to anyone. Especially such as the appearance of a "layer of water" in the desert or on a hot road, caused by the refraction of the rays. Not only children, but also adults can not get rid of the feeling that animals, wells, trees, buildings are real. But, alas!

Light passes through layers of unevenly heated air, creating a unique image of 3D. The mirages are lower (a distant, even surface acquires the appearance of open water), lateral ones (appear next to a highly heated vertical surface), chrono- (reproduce the events of the past).

Northern Lights

Reflecting on what kind of optical phenomena there are, it is impossible not to say about the northern (polar) radiance. It has two main forms: beautiful sparkling ribbons and spots that resemble clouds. Intense radiance, as a rule, is "ribbon". It happens that the colored luminous bands cease to exist, never breaking into components.

In the darkness of the heavenly space, the curtain, as a rule, stretches from east to west. The "trail" can reach several thousand kilometers in width, and several hundred - in height. It is not a dense, but a thin "barrier" through which sparkles sparkle. Very beautiful sight.

The lower edge of the "wings" of the rosaries has a reddish or pink hue, the upper one seems to dissolve in the dark, so that the inexpressible depth of space is well felt. We will discuss four types of auroras.

Homogeneous structure

A calm, simple form of radiance, bright from below and dissolving at the top, is called a uniform arc; Active, mobile, with small folds and streams - a radiant arc. Shining folds superimposed on each other (large to small) are called a "radiant band".

And the fourth kind is when the area from the folds and loops becomes very large. After the end of the activity, the tape acquires a homogeneous structure. There is an opinion that homogeneity is the main property of "his lordship". Folds occur only during a period of increased atmospheric activity.

There are other optical phenomena. Examples are not slow to list below. Flurry is the radiance that gives the entire polar cap a whitish-green glow. It is observed at the southern and northern poles of the Earth, in Iceland, Norway, etc. The phenomenon arises as a result of the glow of magnetized upper layers of the atmosphere when interacting with charged particles of the solar wind (the so-called flow into space of a plasma from helium and hydrogen).

About the light pillars we can say the following: they are frequent in frosty days, very effective.

St. Elm in the crowns of green rays and halo

There are other optical phenomena. For example, a halo, the appearance of which is associated with ice crystals formed in the atmosphere. With the rainbow, it is related by dispersion (decomposition of light into components), only not in a drop, but in the solid structure of ice.

Rainbows are similar to each other, because the drops are the same, they just can, what to fall. The halo has hundreds of species, since the crystals are different and very "bright": they soar, then swirl, then rush to the Earth.

Dreaming once again "deceived", you can admire the false sun (parhelion) or the lights of St. Elm. The latter "sit" on the masts of ships, the sharp tops of tall buildings. Mysticism has nothing to do with it. This is an electrical discharge in the atmosphere. It often occurs during a thunderstorm or in a sandstorm (when the particles are electrified).

Photographers like to catch a "green beam" (flash over the sun and refraction of the rays near the horizon). It is best to capture it in open spaces, in cloudless weather. But the crowns (diffraction of light) are clearly visible when the terrain is clouded by fog (the rainbow circles around the headlights of your car are the crowns), and the sky is covered with a cloud of clouds. In the mist of small droplets, the circles are especially beautiful. When the fog is condensed, they blur. Therefore, the decrease in the number of iridescent rings is regarded as a signal of weather deterioration. What a huge world this is - optical phenomena! The examples analyzed by us are just the tip of the iceberg. Knowing these phenomena, we can scientifically explain any atmospheric illusion.