What is the rotational and translational movement of the Earth?
We are going to explain what the Earth’s rotation is and what effects it produces. The speed it reaches and the translation of the Earth.
What is the rotational movement of the Earth?
This motion allows the planet Earth to rotate on its own axis, i.e. on itself. This axis consists of an imaginary line that crosses the geographic poles and has an inclination of 24° with respect to the Earth’s orbit.
The rotational movement of the Earth takes 24 hours to complete a full rotation, at a speed of 1,700 kilometres per hour (if measured at the equator). We do not feel the movement because it is constant and because we move at the same speed as the Earth, i.e. we are part of the same motion system as the Earth. If the speed of the movement were not constant, we would feel it due to inertia.
Consequences of rotational movement
The Earth’s rotational movement has geographical, climatic, terrestrial and physical consequences. The main ones are:
- Succession of day and night. The Sun illuminates only half of the planet, hence day, while the opposite side remains dark, generating night. As the planet rotates on its own axis, the side that remained dark begins to receive light and the other half becomes dark.
- Time differences. The time zone system consists of a division of the day into hours for the entire planet, and has as its starting point or reference point the zero meridian or Greenwich meridian. This is why sunrise and sunset occur in the eastern hemisphere rather than in the western hemisphere.
- Temperature variation. The succession of day and night means that, during the day, the illuminated side of the planet receives more solar radiation. This energy accumulates and generates an increase in temperature. During the night, when there is no solar radiation, the temperature decreases.
- The shape of the Earth. If the Earth were static, it would be seen as a sphere, i.e. round. As the rotational movement is constant, a centrifugal force is generated which is responsible for flattening the pole area. Due to the rotational movement, the planet is shaped like an ellipse or geoid.
- The cardinal points. The planet’s rotational movement is from west to east and the Sun is at a fixed point, from the Earth it is seen rising in the east at sunrise and setting in the west at sunset. This data is useful for locating the cardinal points if you do not have a compass.
- The Earth’s magnetic field. The rotational movement generates a magnetic field or energy that shields the Earth from solar radiation through the atmosphere (a layer of gases that surrounds the Earth). While the planet and living things need the sun’s light and warmth, some of the sun’s rays are harmful. This magnetic field causes a stream of particles in the atmosphere that blocks them from reaching the Earth’s surface.
What is the speed of the Earth’s rotation?
Depending on the area of the Earth where the speed of rotation is calculated, it varies. But from the equator, the speed is 1,700 km per hour.
As you move away from the equator towards the poles, the speed is slower. For example, at the point at 45 degrees north latitude, the rotational speed is 1,000 km per hour. Above the poles, where the imaginary axis passes, the speed is zero or 0 km per hour.
What is the Earth’s translation movement?
It is when there is a movement between two celestial bodies as the first one rotates its orbit around the second one. In the case of the Earth it is to revolve around the sun. The Earth takes 365 days and 6 hours to complete this translational journey.
When the movement of the earth’s motion interacts with the rotational movement, phenomena such as the succession of the seasons and the length of day and night occur.