Advice 1: Why spinning earth

"Still, it moves!" this encyclopedic phrase uttered by the physicist and astronomer of the last Galileo Galilei, we know from school time. And that is why the Earth revolves? Actually this question is very often asked by their parents as young children, and the adults are not averse to comprehend the mysteries of the Earth's rotation.
For the first time that the Earth revolves around its axis, said in his research, in the early 16th-century Italian scientist. But the reason why the rotation occurs always been a lot of controversy in the scientific community. One of the most common theories says that during the rotation of the earth's main role was played by other processes – those that were in ancient times, when only began the formation of planets. "Huddled together" clouds of cosmic dust, and thus formed the "germ" of the planets. Then "attract" other space bodies – large and smaller. It is the collision with a large celestial bodies, according to some scientists, due to the constant rotation of the planets. And then, according to the theory, the planets continued by inertia rotation. However, if you take into account this theory raises many valid questions. Why in the Solar system of six planets rotate in one direction and another in opposite Venus? Why is the planet Uranus rotates in such a way that on this planet does not change the time of day? Why is the speed of earth's rotation can vary (slightly, of course, but still)? To all these questions scientists have yet to answer. It is known that the Ground tends to slow down its rotation. Each century increases the time of a full revolution about the axis around 0,0024 seconds. Scientists attribute this to the influence of Earth's satellite – the moon. Well, about the planets of the Solar system, we can say that the "slow" rotation of the planet Venus is considered the fastest – Uranium.

Advice 2: Why the Earth rotates

"And still it moves!" - the famous words attributed to Galileo. Our planet doesn't revolve around the sun and around its axis. Why this is happening, put forward many hypotheses, but the General opinion of scholars until he came.
For the first time the Earth's rotation around its axis wrote Copernicus in 1543 treatise "On the circulation of the celestial spheres". But the exact answer to the question of why it was not found until now. The most famous of hypotheses associated with the theory of the origin of the Earth. Through it, our planet was formed from cosmic dust clouds that are "huddled in a heap and formed the nucleus or the center of the Earth. Next to him were drawn of the other cosmic bodies in a collision with that planet started to spin. Continue rotating by inertia.This theory refers to the emergence of not only the Earth but also other planets of the Solar system. This hypothesis cannot explain why six of the planets rotate in one direction, and Venus is the opposite.In addition, until the beginning of XX century it was believed that the Earth rotates at a constant speed and the period of its revolution even took over a unit of time. But the result of long observations revealed that the Earth's rotation is uneven. Happen annual, semiannual, monthly and fortnightly fluctuations of rotational speed during the time which the Earth speeds up and slows down its rotation in thousandths of a second, from-for what duration of day it increases, then decreases. This discovery refutes the theory of the Earth's rotation by inertia and the hypothesis of S. I. Braginsky, in which our planet seems to be a kind of Dynamo-machine.Bind causes the Earth's rotation with external impact on the planet from the Sun. It heats the liquid and gaseous substances on the planet. It happens unevenly and contributes to "air" and "sea" currents. And they, in turn, interact with the crust, move it and affect the acceleration and deceleration of rotation. Scientists have found that during the summer period (June to September) the Earth rotates faster than in other seasons. And after the most powerful solar flare February 25, 1956 our planet suddenly changed the speed of the rotation.
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