The period of revolution of the Earth around its axis is a constant value. Astronomically, it is equal to 23 hours 56 minutes and 4 seconds. However, scientists did not take into account the insignificant error, rounding these figures up to 24 hours, or one Earth day. One such revolution is called a daily rotation and occurs from west to east. For a person from Earth, it looks like morning, afternoon and evening, replacing each other. In other words, the rising of the Sun, noon, and the setting of the sun completely coincide with the daily rotation of the planet.
What is the Earth's axis?
The Earth's axis can be mentally represented as an imaginary line around which the third planet from the Sun revolves. This axis intersects the surface of the Earth at two constant points - at the North and South geographic poles. If, for example, we mentally continue the direction of the earth's axis upwards, then it will pass next to the North Star. By the way, this explains the immobility of the North Star. The effect is created that the celestial sphere moves around the axis, and therefore around thisstars.
Even to a person from Earth, it seems that the starry sky rotates in the direction from east to west. But it's not. The apparent movement is only a reflection of the true diurnal rotation. It is important to know that our planet simultaneously participates in not one, but at least two processes. It revolves around the earth's axis and makes orbital motion around the celestial body.
The apparent movement of the Sun is the same reflection of the true movement of our planet in its orbit around it. As a result, first comes the day, and then - the night. Note that one movement is unthinkable without the other! These are the laws of the universe. Moreover, if the period of revolution of the Earth around its axis is equal to one Earth day, then the time of its movement around the celestial body is a variable value. Let's find out what affects these indicators.
What affects the speed of the Earth's orbital rotation?
The period of revolution of the Earth around its axis is a constant value, which cannot be said about the speed with which the blue planet moves in orbit around the star. For a long time, astronomers thought that this speed was constant. It turned out not! Currently, thanks to the most accurate measuring instruments, scientists have found a slight deviation in the previously obtained figures.
The reason for this variability is the friction that occurs during sea tides. It is it that directly affects the decrease in the orbital speed of the third planet from the Sun. In turn, the ebbs and flows are a consequence of the action on the Earth of its permanent satellite - the Moon. Such a revolution of the planet around the heavenlya person does not notice the luminary, as well as the period of rotation of the Earth around its axis. But we cannot help but pay attention to the change of seasons: spring gives way to summer, summer to autumn, and autumn to winter. And this happens all the time. This is the result of the planet's orbital motion, which lasts 365.25 days, or one Earth year.
It is worth noting that the Earth moves relative to the Sun unevenly. For example, at some points it is closest to the heavenly body, and at others it is the most distant from it. And one more thing: the orbit around the Earth is not a circle, but an oval, or an ellipse.
Why does a person not notice the daily rotation?
Man will never be able to notice the rotation of the planet, being on its surface. This is due to the difference in the size of ours and the globe - it is too huge for us! The period of revolution of the Earth around its axis cannot be noticed in any way, but it will be possible to feel: the day will be replaced by night and vice versa. This has already been discussed above. But what would happen if the blue planet could not rotate around its axis? And here's the thing: on one side of the Earth there would be eternal day, and on the other - eternal night! Terrible, isn't it?
Important to know
So, the period of the Earth's revolution around its axis is almost 24 hours, and the time of its "journey" around the Sun is about 365.25 days (one Earth year), since this value is not constant. Let us draw your attention to the fact that, in addition to the two considered movements, the Earth also participates in others. For example,she, along with the rest of the planets, moves relative to the Milky Way - our native Galaxy. In turn, the Milky Way makes some movement relative to other neighboring galaxies. And everything happens because there has never been and never will be anything immutable and immovable in the Universe! This is something to remember for the rest of your life.
