We know that our planet has numerous types of solar system motion. One of the most important and the one that gives rise to day and night is the movement of earth rotation. It is the rotation of the Earth in an east-west direction around the Earth's axis, lasting approximately one day or 23 hours, 56 minutes, and 3,5 seconds. This movement, along with its orbit around the sun, is the most important movement of the Earth. In particular, rotation has a major impact on the daily lives of living beings.
For this reason, we are going to dedicate this article to telling you everything you need to know about the Earth's rotation and its characteristics.
Key features
The reason why the earth rotates on its axis lies in the origin of the solar system. It could be that the sun spent a lot of time alone after gravity made it possible to emerge from amorphous matter in space. When forming, the Sun acquired the rotation provided by the clouds of primordial material.
Some of the material that causes stars to squeeze around the sun to form planets also acquires angular momentum from the primordial cloud. Thus, all planets (including Earth) have their own east-west rotation, except for Venus and Uranus, that rotate in the opposite direction. To learn more about the different movements of the earth, it is important to analyze how they relate.
Some believe that Uranus collided with another planet of similar density and changed its axis and direction of rotation as a result of the impact. on venus, The presence of gaseous tides could explain why the direction of rotation slowly reverses over time. Furthermore, it is related to the tidal behavior.
Consequences of the terrestrial rotation movement
As mentioned above, the continuity of day and night, and their respective changes in day and temperature, are the most important consequences of the Earth's rotation. However, his influence goes beyond this decisive fact:
- The rotation of the Earth is closely related to the shape of the Earth. The Earth isn't a perfect sphere like a billiard table. As it spins, deformation forces are created that cause the equator to expand and then flatten at the poles.
- The deformation of the Earth causes small fluctuations in the g value of the gravitational acceleration at different places. So, for example, the value of g at the poles is greater than the value at the equator. To understand this better, you can consult the article on terrestrial magnetic field.
- Rotational motion greatly affects the distribution of ocean currents and wind, as air and water masses experience orbital deviations in opposite directions (Southern Hemisphere), clockwise (Northern Hemisphere), and clockwise (Northern Hemisphere). To learn more about this phenomenon, we recommend reading about the Coriolis effect.
- The constellations They have been created to regulate the passage of time in each place as the sun illuminates or darkens different areas of the earth.
Coriolis effect on Earth's rotation
The Coriolis effect is the result of the Earth's rotation. Since all rotations have acceleration, the Earth is not considered an inertial reference frame, which is required to apply Newton's laws.
In this case, so-called pseudo-forces arise, where the source of the force is not physical, such as the centrifugal force experienced by the occupants of a car when cornering, and they feel as if they are skewed to one side.
To visualize its effect, consider the following example: There are two people A and B on a platform rotating counterclockwise, both stationary relative to it. Person A throws the ball to person B, but by the time the ball reaches B, he has moved and the ball deflects a distance s behind B.
Centrifugal force doesn't matter in this case because it's far from the center. This is the Coriolis force, and its effect is to deflect the ball sideways. It just so happens that both A and B have different upward velocities because they're at different distances from the axis of rotation. If you're interested in the impact of this effect, you can read more about it in our articles.
Other movements of the Earth
Translation
We proceed to analyze the second most complex movement of the Earth. It is the movement that the Earth has that consists of making a turn in its orbit around the Sun. This orbit describes an elliptical movement and makes it closer to the Sun and sometimes further away.
The Earth takes 365 days, 5 hours, 48 minutes, and 45 seconds to complete a full rotation on its axis. Therefore, every four years we have a leap year in which February has one more day. This is done to adjust the schedules and ensure they remain stable. To better understand the rotation and its deceleration, we recommend visiting the article on the rotation of the Earth.
The Earth's orbit about the Sun has a perimeter of 938 million kilometers and is kept at an average distance of 150 km from it. The speed at which we travel is 000 km / h. Despite being a great speed, we do not appreciate it thanks to Earth's gravity.
Precession
It is the slow and gradual change that the Earth has in the orientation of the axis of rotation. This motion is called precession of the Earth and is caused by the moment of force exerted by the Earth-Sun system. This movement directly affects the inclination with which The sun's rays reach the earth's surface. Currently this axis has an inclination of 23,43 degrees.
This tells us that the Earth's axis of rotation does not always point to the same star (Polar), but that it rotates clockwise, causing the Earth to move in a movement similar to that of a top. One complete revolution in the precession axis takes about 25.700 years. Therefore, it is not something appreciable on a human scale. However, if we measure it with geological time, we can see that it has great relevance during periods of glaciation. For more information on these geological events, see the article on glaciations.
I hope that with this information you can learn more about the movement of the earth's rotation and its characteristics.