There are many round objects in our sky. The view of the many balls around us is astonishing, and we involuntarily ask: “Why should the stars really not be small dots in the sky? Or why not be at least one non-circular planet? ”
Well, let one, only one, be cubic or pyramidal. Why is this impossible? And here is why. There is a force that in the entire universe turns the worlds into smooth balls. This force is gravity, that is, gravity, or, more precisely, gravity.
Gravity
Gravity is the force that attracts any piece of matter to another. This is the force that makes the ball fall to the ground and keeps the planets in their orbits. The larger the mass of the object, the greater its gravity, that is, gravity. However eIf we compare the force of gravity with electromagnetic forces, then gravity is much weaker. Therefore, we do not notice the forces of gravity between people in a crowd or between a hand and a pencil. A pencil and a person have not too large masses.
But drop the pencil and see gravity in action. The pencil will not fly up and will not fly to the side. It will fall exactly down towards the ground. The force of gravity of the earth acts on the pencil. Compared to a pencil, the earth is a huge material body, the mass of which is incredibly large in relation to the mass of the pencil. To feel the force of gravity, just jump.And you will feel with what inexorable force mother attracts you - the earth.
Why do planets get round?
Gravity seeks to hold objects together, for example, nine planets of the solar system, which were formed from the collision of small particles of world dust about 4.6 billion years ago. As the planets grew, so did the force of attraction between their parts. They attracted more matter from outer space, and their mass grew. A good example of this process is meteorites falling on Earth.
Interesting fact: as the planets grow, gravity turns them into a ball, they become round.
As the planet grows, gravity tends to turn it into a ball. The more the planet grows, the stronger its gravity. All new and new parts of matter are added to the planet and spread out on its surface. As a result of this process, a round body is formed. Although gravity forms spherical planets, there are protrusions on their surface. From space, the Earth looks almost perfectly white - blue sphere. But when approaching it, high mountains that protrude above the surface of the earth become noticeable. From even closer distances, buildings and people become visible.
Gravity (gravity) and planetary landscape
The Earth's gravitational force is not enough to smear people and mountains on its surface. But there is a certain limit beyond which the mountains cannot grow, since the earth's crust can withstand not too much gravity. Our neighbor Mars is a planet smaller than Earth.The gravitational force of Mars is three times less than the gravity of the Earth. Therefore, the geological structures of Mars can reach incredible heights in terrestrial terms.
This, according to experts from the National Aeronautics and Space Administration (NASA), explains that Olympus, the highest peak in Mars, has a height of 24,000 meters. It is almost three times higher than Everest. This peak of Mars was called Olympus, since, according to ancient Greek mythology, Olympus is a high mountain on which the gods, inaccessible to mortal people, lived.
On a planet more massive than Mars or Earth, where the force of gravity is ten times greater than Earth's, the landscape will be flatter, animals small and squat. A giraffe with its long neck would feel very uncomfortable on such a planet. Sometimes the gravitational force of a cosmic body can change the shape of another, closely spaced.
For example, scientists believe that one blue supergiant star rotates around its invisible neighbor - a black hole. A black hole (sometimes it is formed from an extinct star) is a body with such high gravity that no light is emitted from its surface that cannot overcome the force of gravity.
Gases flowing from the surface of a star are attracted by a black hole and fall on its surface. A rotating black dwarf pulls a stellar wind. This stream of particles carries along the substance of the star, and its shape changes - it becomes more elongated. On the other hand, small lightweight cosmic bodies in shape often do not even remotely resemble a ball. Their gravity is clearly not enough to turn them into spherical bodies. So, some asteroids resemble the shape of a mountain.Phobos, a satellite of Mars, looks like a round potato.
