From birth, a person gets used to the fact that the sky above his head can be of different colors. Why is this happening? Why at night the sky, decorated with many stars, becomes completely black or blue-violet? Why is it blue during the day, but becomes foggy and gray when it is covered in thick clouds? Why are shades of lilac, red and yellow visible in the sky during sunset or dawn? Answering these questions, you need to understand what is heaven scientifically.
What is the sky?
From the point of view of science, the sky is space above the planet, a panorama that opens when viewed from its surface upward, towards space. The structure of the sky is made up of atmospheric layers. Physical processes are accompanied by the appearance of clouds, clouds, showers and thunderstorms.
The sky above the Earth and above other planets is a shell that appears in various colors when viewed into space. And each planet has its own color scheme of the sky. For a long time there are definitions of the Earth's sky, Lunar, Martian and others. The difference between the sky above each cosmic body is determined by the uniqueness of the atmosphere of each of these bodies. The molecular composition of the atmosphere, which determines which processes will occur on a particular planet, is unique to each cosmic body.
What determines the view of the sky?
Thus, the atmosphere of Mars is not able to delay various meteorites and other bodies from outer space, so on this planet it is often possible to observe meteor showers and significant temperature differences. The color of the sky on Mars has a reddish hue, since the atmosphere here contains microscopic metallic compounds.
Unlike the atmosphere of Mars, the Earth’s atmosphere has many layers that reliably protect the planet from foreign cosmic bodies. The presence of the ozone layer and oxygen molecules in the atmosphere also contributes to this. Therefore, the fall of a meteorite to Earth is an exceptional event, equating to a global catastrophe. In addition, the Earth’s atmosphere protects its planet from interstellar dust and sudden changes in temperature.
Factors affecting the appearance of the sky
Science has established a number of factors that influence how the sky looks. These factors include:
- composition of the atmosphere;
- weather;
- season;
- Times of Day;
- place of observation of the sky.
Cosmic bodies in the sky above the Earth
In order to characterize the vast number of cosmic bodies that can be seen at night, there is a special term “starry sky”. For example, constellations belong to starry sky areas. They were discovered by people in antiquity with the aim of studying the sky. This discovery made it possible to easily recognize every part of the starry sky. In addition, with the help of constellations, it has become easier to measure time and navigate the terrain. This knowledge could be applied in agriculture.
The constellations themselves are represented as figures of animals and mythical characters. In the starry sky, they seem to be close to each other, but in reality there can be a huge distance between them. Stars, united by people in a single constellation, may not be connected at all with one another, being both close to the Earth and very far away.
Among the stars in the clear sky you can often see the moon. In the afternoon, instead of the moon, the sun is visible in the sky. If clouds are floating in the sky, then from above they will resemble whipped cream, and the surface of the Earth may not be visible at all. If you look at the thunderclouds from above, an even more magnificent picture will open than when observing a thunderstorm from the ground.
Why is the sky colorful?
From different points of the Earth, the sky looks different. A clear daytime sky has blue hues in every corner of the planet. Hues become more saturated on sunny days. And, on the contrary, during the period of cloudy sky filled with more pale shades.The shape of the sky in a particular region depends on the location of the clouds, they are in a certain place and quite close to the surface of the Earth.
An interesting fact is that the clouds only seem airy and weightless. They travel freely and smoothly through the sky, despite the fact that the average cloud weighs about ten tons. This is possible due to the fact that the weight of the cloud is distributed between drops of water and small ice crystals. Moreover, the lifetime of the clouds is limited.
For a longer life, the clouds require high humidity. At low humidity, clouds evaporate. There are times when the cloud completely evaporates within 15 minutes. If the humidity is high, then the cloud will exist for a long time, however, the probability of precipitation is high.
Time of day is another factor, depending on which the color of the sky changes in absolutely all regions.
Phenomena associated with a change in the color of the sky, in accordance with the laws of physics, are explained by refraction and scattering of light. Moreover, the longer the wavelength of a particular color, the faster it dissipates. So, in the afternoon, sunlight falls vertically on the Earth, its particles are scattered in such a way that a person sees only blue and violet shades that have a short wavelength. During dawn or sunset, the rays of the sun fall to the earth at a different angle so that the blue waves do not hit the earth's surface. As a result, the sky is saturated with red shades.
Physico-astronomical theory of the sky
Despite the greater number of stars in outer space, the Sun is the only celestial body that is close enough and bright enough to affect the color of the sky above the Earth.
It is important to know the fact that the Sun is about 4.5 billion years old. In about the same amount, it will turn into an extinct star called the “white dwarf”. By this moment, all the planets of the solar system have cooled down and will already revolve around an extinct star.
At this point in time, the conversion of hydrogen to helium occurs in the core of the sun. When hydrogen, which now makes up 73% of the mass of this star, completely burns out, a gradual increase in the radius of the Sun will begin. Stars at this stage are called the "red giant" and are a fireball of gigantic proportions.
The sun will continue to expand approximately to the orbit of Venus, after which several states will pass, after which nuclear reactions will completely cease. The passage of these stages will lead the Sun to the “white dwarf” state. This star will have about 100 times smaller radius and 100-1000 times less capacity than the sun has today.
All these calculations are based on scientific research. For this, astronomers analyzed the mass of the Sun and the rate of nuclear reactions. As a result, it was determined for how long hydrogen would be enough inside the Sun for the full functioning of this star.
As noted, the planets of the solar system will also cool. Mercury and Venus will be absorbed at the stage of the red giant, and the red-hot atmosphere of the Sun will also absorb the Earth. At the same time, conditions suitable for life may well appear on Mars, since this expansion will not reach it. Thus, until the sun goes out completely, the remnants of the surviving planets, such as Mars, Jupiter and Saturn, will revolve around it.
The sky that we see on our planet
Returning to the analysis of the relationship between the Sun and the Earth's sky, it is necessary to say that blue and red are not the only parts of the color spectrum into which sunlight breaks down. This spectrum includes all the colors of the rainbow. However, passing through the atmosphere and colliding with various particles in the air, the rays of the spectrum change their direction. In this case, the sun's rays themselves have a white color, in which the sky would have colored if all parts of the spectrum reached the Earth.However, various processes allow you to go all the way only blue and blue waves.
Particles that are in the air and prevent light waves from reaching the Earth's surface are various gases, as well as drops of water and ice. Gas molecules absorb the photons of sunlight and produce their own, secondary photons. The color scheme of these new photons can be absolutely any. In addition, their wavelength and direction of movement are different.
Science has proved that secondary blue photons are found eight times more often than red photons. Thus, the blue color of the sky is largely due to the influence of atmospheric gases.
Our closest companion
Cosmic bodies that can be seen while on Earth are differently approximated to the equator and to the poles. This also applies to the natural satellite of the Earth - the moon. At the equator, it is visible better, it becomes larger in size to such an extent that you can see its craters and oceans. Also at the equator you can often see the blue or blue moon, which in other regions is quite rare. This explains the fact that scientists observe cosmic bodies precisely from equatorial latitudes.
The role of heaven in mythology
Historically, it was heaven that was the place that people endowed with various magical properties. There are several mythologies in which heaven and earth are endowed with divine powers. The Egyptians called them Noob and Gaia, the ancient Greeks - Uranus and Gaia. Other mythologies claimed that heaven is the habitat of the gods or souls of the dead.
Some modern religious movements base their teachings on the basis of scientific knowledge. So, in Christianity, the term "heaven" exists, which symbolizes the habitat of angels and souls. Heaven got its name due to the majesty of the blue sky spreading over the Earth.
The development of science has helped dispel almost all of these myths. Man was able to explore not only the sky. Currently, outer space is being actively explored, which stores even more mysteries.
