Knowing the center of our planet has been a topic of global interest for centuries. It was not for nothing that the legendary Jules Verne took the risk of writing about how to get there. A rather unlikely mission if you take into account gravity at the center of the Earth, a phenomenon that makes up one of the basic laws of the Universe, one of the four fundamental interactions of matter along with electromagnetism and the strong and weak nuclear interaction forces.
As we well know thanks to so many scholars who, like us, were interested in knowing what happens on the planet (beyond human life), as far as physics is concerned, terrestrial gravity – a point that we are interested in dealing with – is the force that makes things fall with a given acceleration constant towards Earth and keeps us moving smoothly without “falling” into space.
The renowned physicist and mathematician Isaac Newton was the first to be interested in this phenomenon and later to explain it, Furthermore, he specified that gravity is, in turn, the force that keeps the planets and other celestial bodies in motion. The way it acts depends on various factors, which is why it is so different here on Earth than it is in outer space. In reality, it all depends on the amount of mass and the distance between the bodies.
It may interest you: What did Newton discover about gravity and what did he contribute to physics?
The attraction between particles that governs gravity causes bodies to be attracted to a surface and is what makes it possible for all of us to walk peacefully without floating off into space. Now, we know that this is what happens on the surface of the earth, we stay in our place, but… what happens to gravity at the center of the earth? Given the difference in atmospheric pressure and temperature, how is gravity there? To satisfy your curiosity about this phenomenon and its actions in the center of the sphere, we bring you four amazing facts about gravity on planet Earth.
Gravity at the center of the Earth determines its depth
The mass of the Earth is 5,9 sextillion tons. That key number could only be thrown after observing the effect of gravity on objects located on the surface (supported by data from earthquakes and nuclear bomb launches), where, according to scientist Simon Redfern, the density of the material is much lower than the average density of the entire Earth. "That tells us there's something much denser."
That "something" is, according to various scholars, 80% iron. All concentrated in the center of the planet. In addition to allowing us to know these data, gravity tells us what is the depth of the center of the Earth: more than 6.000 km. A gigantic distance to which the human being has never approached, not even to the external zone of him, which is about 3.000 km below our feet. Gravity at the center of the Earth is a fascinating subject, where it is also important to consider these data.
The closest we have been to the center of the Earth (if you could say "close") is with the creation of the Kola Superdeep Well in Russia, the deepest hole ever drilled, is only 12,3 km deep.. With this data it seems even more unlikely to reach the center of the sphere, remembering the aforementioned atmospheric pressure and temperature, which already represent an impediment per se.
The intensity of the gravitational field is smaller at the equator.
Because gravity decreases with distance and the Earth is not a perfectly spherical planet, (it is flattened at the poles) At the equator there is a lower gravitational field strength. Likewise, the gravitational intensity between areas located at the same latitude is affected by the presence of mountains or rock compositions with greater or lesser density. It is also interesting to observe how gravity and magnetism They act together with these factors in different parts of the planet.
Adding in the effect of rotation, there is a 5% difference between gravity at the poles (which is approximately 9.832 m/s2) and that at the equator (9.789 m/s2). At the surface of the Earth's core, the intensity of the gravitational field increases to 10.7 m/s2, while the gravity in the center of the Earth is null because the intensity of that field is of a vectorial magnitude that reaching the center of the sphere all vectors cancel.
Gravity at the center of the Earth is not perceived
The gravity that we normally perceive, the one that keeps us with our feet on the Earth, comes precisely from its mass, which makes us feel that it is pulling us towards it, with force. According to theory, this boils down to The force of gravity is determined by the mass of the object and the proximity between it and another, that is, the greater the mass and the greater the proximity, the greater the force. If you are interested in learning more about the characteristics of gravity, you can read about what is the force of gravity.
This situation varies when it comes to gravity at the center of the Earth, due to its spherical shape, the blue planet causes gravitational forces to interact with each other. For this reason, it is assumed that there we would not feel any type of gravity force, since all the mass that is in it would pull us in all directions and the total force would be zero. you already know, the sum of all forces is 0.
While on the surface of the Earth's core, the intensity of the gravitational field increases to 10.7 m/s2. In this sense, a curious fact is that the Earth and the Sun remain connected by gravity, which absorbs them and keeps them close. This is how The center of gravity of the earth is the middle of the mass of the Earth and the Sun., which is roughly at the center of the Sun. You can learn more about this topic at the center of gravity.
Traveling through the center of the Earth could take you 42 minutes
Very hypothetically can travel through the center of the Earth in just 42 minutes. This would be achieved by tunneling from one side of the planet to the other, crossing through the center. By throwing yourself through the hole, the force of gravity would make you fall quickly until you passed the midpoint, in which the body would begin to slow down until you reach the exit with the same speed with which you entered.
According to this estimate, published in TIME magazine as To Everywhere in 42 Minutes, with an initial velocity of 0, the elapsed time would be only 42 minutes, the same time it would take if the tunnel were between two points that do not pass through the center of the sphere. This would be because gravity would pull the body at an angle, so the acceleration in the direction of the aforementioned tunnel would be lower, and therefore the maximum velocity would be lower as well.
Despite the many data that have been obtained on gravity in the center of the Earth, much remains to be discovered. Thanks to the force of gravity, and studies related to phenomena such as earthquakes and the waves deployed by the operation of nuclear weapons, it has been possible to know more about the center of the planet, however, it seems impossible to overcome those 6.000 km of depth between our surface and the core of the spherical. It will continue as a slope for the human being to verify in his own flesh the gravity in the center of the Earth.
