Like all the planets of our huge Solarsystem, the Earth makes two main turns - around its axis and around the Sun. The time of one revolution of the Earth around the axis is called day, and the period for which it orbits around its Sun is a year. This movement is the guarantee of life and physical laws on the planet, by which we all exist. At the slightest failure (which has not happened so far), the work of all spheres of the Earth, ecosystems and living organisms will be disrupted.
And in the people, and in science, the time of one revolution of the Eartharound the axis called day. They consist of day and night, which take an average of 24 hours. Our planet rotates counter-clockwise, that is, from west to east. It is because of this that the inhabitants of the eastern regions meet the dawn first, while the inhabitants of the western hemisphere are the last. The axis is called the conditional line, which passes through the south and north poles of the planet. Thus, these extreme points do not feel in the process of rotation, while all other parts of the earth move.
Since the motion of the planet is made from the westto the east, we can observe how the entire celestial sphere as if passes us in the opposite direction, that is, from east to west. This applies to the Sun and all the stars that we see at night. The exception is the moon, since it is an earth satellite having an individual orbit.
It is the diurnal period that determines the speedrotation of the Earth around the axis. Within 24 hours, this celestial body must perform a complete treatment taking into account its own parameters and mass. We have already said that the axis pierces the Earth from north to south, and during this process the poles do not rotate around it. At this time, all other zones, including circumpolar and equatorial, move at a certain rate. The speed of Earth's rotation in the equatorial region is maximal. It reaches 1670 km / h. In this area, day and night have an equal number of hours throughout the year.
The speed of Earth's rotation in Italy on averageIt reaches 1200 km / h with a seasonal change in the duration of the day and night. Thus, the closer we move to the poles, the slower the planet rotates there, gradually coming to zero.
The time of one revolution of the Earth around the axis is calledday, and put in this period exactly 24 hours. But it is worth remembering that there are such concepts as solar day and sidereal, which have a small but significant difference.
To begin with, we consider all the features of the firsttype. Firstly, not every day of our life lasts exactly 24 hours. In those moments when the planet approaches the Sun, its rotation speed around the axis increases. In periods of separation from the main luminary of the system, the motion of the planet Earth slows down. Therefore, in summer, a day can flow a little faster, and in winter they last longer.
As for the sidereal days, theirthe duration is 23 hours, 56 minutes and 4 seconds. This is the time for which our planet makes its rotation around the axis with respect to some distant star. That is, if the distant star turned out to be the Sun, then the whole revolution, consisting of 360 degrees, would be complete for this period. But in order for it to reach the end of the Sun itself, it is necessary to go one more degree, which takes just four minutes.
The Earth circles the Sun in an elliptical orbit.That is, its treatment is not based on a clear form of the circle, but on an oval scheme. The speed of the Earth's motion around the Sun averages 107,000 km / h, but this unit is unstable. The average distance of our planet from the star is 150 million kilometers. The degree of inclination of the earth's axis relative to the orbit is considered to be an exact and unchanging unit - 66 degrees and 33 seconds, regardless of the time of day and year. It is this inclination, coupled with the shape of the orbit, the variable speed of movement and circulation, that enables us to feel seasonal climate changes, but not in all latitudes. If the daily fluctuations in time and any changes are multiplied by zero in the region of the poles, the seasonal features also freeze at the equator. Every day from year to year there passes the same way as the previous one, with the same weather, as well as the duration of the day and night.
The term "ecliptic" refers to the cross-sectionthe celestial sphere that is within the orbits of the Earth and the Moon. Within the boundaries of this conditional circle, all the major movements of our planet take place, as well as the revolution of the moon around it. It should be noted that the latter has considerable influence on the climate, the hydrosphere and the atmosphere of the Earth. The moon can be the cause of eclipses, tides and tides, lithospheric metamorphosis and much more.
As for the ecliptic itself, this planehas its heavenly equator, which has certain astronomical coordinates. Relative to them, the slope of all the planets of the solar system is calculated. Similarly, the position of the stars and galaxies that we see in the sky is calculated (after all, their light falls into the ecliptic, hence all the celestial bodies viewed are a part of it). This theory is the basis of astrology. In accordance with this science, those constellations that pass through the ecliptic are the Zodiac. The only unit that does not belong to this category is Ophiuchus. This constellation is seen in the sky, but it is not in the astrological tables.
We determined that the time of one revolution of the Eartharound the axis called day. The latter are sunny (24 hours) or sidereal (23 hours 56 minutes). The change of day and night occurs in all latitudes of the planet except for the poles. There, the earth's rotation speed is zero. The planet revolves around the Sun in a year - 365 days. During this period there is a change of seasons in all corners of the Earth, but not at the equator. This zone is the most stable, while it rotates around its axis at maximum speed.
