Our solar system is made up of planets and their satellites that revolve in their orbits around the sun. During the creation of this solar system and during the creation of the planets there were various forces that caused the planets to acquire a round shape. many people wonder why are the planets round and how they were formed.
For this reason, we are going to dedicate this article to telling you why the planets are round, what their characteristics are, and how they originated to have this shape.
Why are the planets round?
Since the dawn of astronomical observations, humans have been interested in studying the objects we see in the night sky and trying to figure out why they form. These planets are part of this group of objects of interest. It has been known since ancient times that these points in the sky have a roughly circular shape, and we also know that we inhabit one of them. This information has been preserved to this day, although now we can say that we have a better understanding of the physical processes and factors that affect the shape of the planets.
The answer to this question is easier than you think, and basically lies in its formation and severity. Gravity pulls from the center toward the edges, which is why planets are often shaped like a sphere, which is a three-dimensional circle.
During the formation of planets, planets consist of molten matter and extremely hot liquids. Since gravity always pulls an object's mass toward its center, the material this liquid is made of is compressed into an imperfect sphere with a few bulges. When the planet cooled, they solidified.
Planets are round because their gravitational field acts as if it originates from the center of the body and pulls everything towards it. A planet's gravity pulls equally in all directions. Gravity pulls from the center to the edges like the spokes of a bicycle wheel. This makes the general shape of the planet a sphere, which is a three-dimensional circle.
Are they a perfect sphere?
In our solar system, the planets look very beautiful, they are almost a perfect sphere, especially Mercury, Venus and the Earth itself. In fact, if we put it on the scale of a billiard ball, we couldn't tell the blemishes. The answer, however, is that the planets are not perfect spheres.
Planets can collide with other celestial bodies, creating craters or bulges in the shape of their surfaces. Also, since they are constantly rotating, some spherical shaped bumps are created. When something spins, like a planet, things on the outer edge have to move faster than things on the inside to keep up, and they bulge along the equator as a result.
The faster the planet is, the bigger the bulge is, depending on how fast the planet is spinning.. Conversely, the slower a planet moves, the fewer irregularities it will exhibit in its shape. Without going any further, Saturn and Jupiter are a little thicker in the center due to their speed of rotation.
There are other more irregular objects in space, and they are the smallest. These do not enter our discussion because they do not fall into the category of planets. In 2006, the International Astronomical Union classified a planet in this category, which must meet certain characteristics:
- must orbit a star
- It must be large enough that its gravity causes it to assume a spherical shape.
- It has to be big enough for its gravitational pull to knock out any other objects of its size orbiting closer to the Sun.
Not all planets are equally round
First, let's review the planets in our solar system. Here are eight, which we refer to as the smallest to greatest distances from the sun: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
It is a curious fact that it is necessary to know that not all planets are equicircular. For example, Mercury and Venus are the roundest. Among them it can be said that they are almost perfect spheres.
By contrast, Saturn and Jupiter are "less round" because they are slightly thicker in the middle. What happens is that as they spin, they bulge along the equator.
In the chaos of Earth and Mars, one would have to say that they are smaller than Saturn or Jupiter, and that they do not spin as fast as the gas giants (Jupiter, Saturn, Uranus and Neptune). Earth is 0,3% thicker in the east and Mars is 0,6% thicker in the center, so they are not perfect spheres, but rounder than Saturn and Jupiter.
Even closer to the perfect spheres are Uranus and Neptune. The former is 2,3% thicker in the middle and the latter is 1,7% thicker. So they're not quite as perfect as Mercury and Venus, but they're pretty close.
Formation of the planets
Planets form when matter in space begins to collide and stick together. After a while you have enough material to generate a decent amount of gravity. That is the force that unites things in space. When a forming planet is large enough, it begins to clear the path of the star it orbits. It uses its gravity to catch fragments of space material.
Therefore, the spherical shape of large celestial bodies is due to gravitation. Any object creates a gravitational field around itself, as if the entire mass of the body is concentrated in the center and attracts matter to itself. During the long course of a planet's formation, matter flowed, affected by the heat of its internal nuclear reactions, and succumbed to the powerful pull of its gravitational center. A spherical distribution is symmetric in all directions and is the only geometry that keeps all matter on Earth as close to its center as possible.
The planet's gravity pulls equally from all directions. Gravity pulls from the center to the edges like the spokes of a bicycle wheel. This makes the general shape of the planet a sphere, a three-dimensional circle.
I hope that with this information you can learn more about why the planets are round and their characteristics.