However, even accepted conclusions deserve critical thinking. Our earth has more than 8,000 meters of Himalayas and more than 10,000 meters of Mariana Trench. How can we say that the earth is round?
our earth
First we need to understand the beautiful blue planet Earth.
The earth is our only home, and all the sense of belonging about home belongs to it, but it is one in a billion in the universe, one of the splendid galaxy, but this does not affect our love for it.
In the solar system, according to the distance from the sun as the standard, it ranks third among the eight planets, Mercury and Venus are in front of it, and Mars and Jupiter are behind it.
Its position from the sun can be said to be unique. It is not too far away, and it is unbearably cold, just like Mars, and it is not too close, and it is deeply scorched, just like Mercury. This has also become a major advantage for the earth to breed life.
In the entire universe, the earth is currently the only planet with life, and our earth is alone in the universe.
The alias of the earth is the blue planet, because about 70% of its surface is covered by water bodies such as oceans, lakes, and rivers. Most of the polar regions are also covered by ice, and only 30% are land. From outer space, it looks like Water world, blue ocean.
The structure of the earth is not complicated, it has a certain level, and the inside is a concentric circle structure.
According to the different propagation speed of seismic waves in each structural layer, from the inside to the outside, it can be divided into several layers: the core, the mantle, and the crust. Although these structural layers are millions of years old, they are still alive and tectonic plates are moving.
It is precisely because of this that the surface of our earth is not static, and it is still changing today, but this change is far beyond the life cycle of human beings, and it is difficult for us to perceive it. Fortunately, modern science and technology allow us to discover and analyze the geological changes on the earth and decipher the vicissitudes of life.
There is a circle of atmosphere on the outside of the earth, which plays an important role in maintaining the stability of the earth’s climate, mild weather and life.
However, the earth did not have an atmosphere from the beginning, but gradually formed an atmosphere over a long period of time, supported by chemical reactions such as photosynthesis of plants.
Earth’s atmosphere is mainly composed of two gases, nitrogen and oxygen. With the atmosphere and the effect of solar radiation, the three circles of the earth began to form a water cycle, and the water of life has a long history in human life.
Is the rolling earth round?
There was once a so-called “no makeup photo” of the earth on the Internet. In the photo, the earth is not only not round, but also irregular like a potato, with bumps and bumps, which is said to be the earth after the water has been drained.
Many people began to question whether the earth is round, causing heated discussions among netizens. Is the earth really so irregular, even a little ugly?
We live on the earth, and it is difficult to directly see the shape of the earth, so we need to use advanced observation tools and calculation methods.
After the Age of Navigation, people have proved that the earth is round by sailing, but they have not been able to provide a clear image of the earth. In modern times, people use space telescopes and spacecraft to take pictures of the earth directly in outer space, revealing the mystery of the earth’s image.
Scientists give this evaluation, the earth is a sphere, but not a true sphere, the poles are slightly flat, and the equator is slightly bulging.
Specifically, the radius of the earth is about 6371 kilometers, while the average radius of the poles of the earth is 6356, and the equator is 6378 kilometers. The radius of the poles is 22 kilometers smaller than the equator, and there is still a slight gap.
The “undressed photos” of the earth circulating on the Internet are not the earth after the water has been drained, but the distribution map of the gravitational field. Of course, it cannot be regarded as a diagram of the appearance of the earth.
However, according to scientists, the shape of the earth is not very symmetrical, like a pear. So is the earth really not round?
In fact, the earth is still round. Because the size of the earth is too large, it is completely invisible when compared with this little bit of asymmetry.
Although there is a gap of 22 kilometers between the polar radius of the earth and the equatorial radius, it is already very large in our opinion, but from the perspective of the entire earth, these 22 kilometers only account for 3% of the average radius of the earth, which can be said to be insignificant. It’s like grinding a millimeter off a basketball, and the naked eye can’t see it at all.
Similarly, Mount Everest is more than 8,000 meters high, and it is still increasing. This is a very high height for us humans. The deepest trench is more than 10,000 meters deep, which is also a very high altitude for humans, but it is very high for humans. The whole earth is also insignificant.
The height of Mount Everest is only about 1% of the average radius of the earth, which is 1 centimeter less in 100 meters, and it is difficult to notice.
Why are celestial bodies generally round?
When we look up at the starry sky at night, we will find that the stars are like dots. In fact, not only our earth, but most of the celestial bodies are spheres. Why is this? This is the power of gravity.
There are four fundamental forces in the universe, of which gravitation is the weakest, but it is very closely related to human beings. Tides, falling objects, etc. are all inseparable from gravity. Gravity is a long-range force, and there is no corresponding “repulsive force”, so gravity can be superimposed infinitely, which has a great impact on celestial bodies.
According to Newton’s law of universal gravitation, we know that gravity and mass are proportional, so when the mass of an object reaches a certain level, the gravitational force it produces can make matter behave like a fluid.
Therefore, the material surface of the celestial body can be shaped, and when the material reaches the hydrostatic equilibrium, it will gradually evolve into a sphere.
Epilogue
Earth is our only home, and our curiosity, enthusiasm for it is always abundant, and even proven scientific conclusions can be challenged again. Because we have not reached the eternal truth, we are only approaching the truth.
GIPHY App Key not set. Please check settings