Earth arose, spinning. Particles of matter in this rotating cloud also rotated and colliding, connecting with each other, formed larger, also rotating bodies.
Rotation of objects in space
Today, planets move around the Sun in the same direction as the vortex cloud that gave rise to them. Asteroids - planetary waste products - also revolve around their axes, moving in space. The period of revolution of large asteroids, that is, the time during which they make one revolution around the axis, is 5-18 hours. More than 4 billion years ago, the duration of the earth's day was about 6 hours. In millions of years, it will probably be 1,128 hours.
The Earth’s revolution is 24 hours. The circumference of the Earth is about 40,000 kilometers. Thus, the linear speed of the Earth's rotation at the equator is approximately 1,600 kilometers per hour. So says William Hartman, an astronomer at the Planetary Science Institute in Tucson, Arizona.
Earth rotates from west to east. They try to build spaceports for launches of artificial Earth satellites as close to the equator as possible. Satellites launch eastward. This gives the satellite an increase in the initial speed of 1,600 kilometers per hour.
Why does the Earth’s rotation not slow down?
Earth's rotation is still slowing. When our planet was just forming, it rotated much faster.The linear speed of its rotation at the equator was then about 6,400 kilometers per hour. This means that the day lasted only 6 hours. If people lived on Earth then, they would see the Sun rise and then set in 3 hours, leaving them a three-hour night to sleep.
The length of the day on Mercury is about two earth months. The giant Jupiter rotates so fast that a day on it lasts less than 10 hours. The days of Mars are equal to ours - they last 24 hours 37 minutes.
The moon, at that time, was much closer to Earth than it is now. Moreover, she gradually, but steadily away from the Earth. The force of gravity of the Moon, acting on the Earth, forces ocean waters to rise and fall. These oceanic tides hinder the rotation of the Earth year after year. Every hundred years, the day is extended by half a minute. A day will stretch over time to 1128 hours. Due to the action of gravitational forces and tides, the Moon will begin to approach the Earth, and its rotation speed will increase again.
