Strange but true, the world is not round and the world is flat! But due to “certain forces in physics” the world has a strange shape than expected.
When various space organizations release images of Earth taken from space It gives us an arc that appears to be perfectly rounded and beautiful. Not only that, the pictures of the planets in the solar system make us feel that everything is perfectly round. But actually Those planets include Earth. It’s not quite like that.
.
Aristotle and other ancient Greek scholars were among the first to suggest that the world was round by observing the surroundings such as Ships sailing out into the ocean don’t just look smaller. But it also seemed to sink into the horizon.
If the world were truly flat, ships should all travel in the same plane. This created intense debate from all sides. But humanity eventually realized that the earth was indeed round, but it was believed to be a perfect sphere.
.
Why is the world round?
In short, the gravity of matter pulls everything as close to the center as possible. Points that are further from the center are pulled down as far as gravity allows. Because of this, any object that is large enough becomes spherical. This is because a sphere is a shape in which gravity is distributed equally in all areas.
.
“But the point is, gravity is actually surprisingly weak. The object must be very large first. before a strong enough gravitational force can be created to overcome the strength of the material,” said Jonti Horner, professor of astrophysics. from the University of Southern Queensland said
.
The world itself is the same. It is large enough to create gravity pulling matter into spheres. But it is weak enough to succumb to another force caused by the Earth’s rotation. Jean Richter, an astronomer from France, noticed this anomaly.
.
In 1671, he traveled to Cayenne, French Guiana, in South America, taking with him a pendulum clock that kept the normal time in Paris. But when he arrived in South America The pendulum clock slowed down. It cost him 2 and a half minutes every day. So he shortened it. But when he returned to Paris It was found that the same clock was running two and a half minutes too fast each day.
.
This irritated Richter greatly. But it did make mathematician Christian Huygens think of something. That is, this watch is evidence that the world is spinning. And that rotation gave the Earth its strange shape. Isaac Newton later proved it mathematically in a book known as ‘The Principia’.
.
This indicates that the Earth is not perfectly round but instead ‘bulges out’ around the equator. “Most planets and moons are not truly spherical,” said NASA planetary scientist James Tuttle Keane. “They are often compressed in some way.”
.
And what squeezes the Earth and other planets is ‘centrifugal force’, which is a force that everyone has probably experienced. When we sit in a ride that spins around itself We will feel like we are being thrown outside. Arms, legs, or hair will be thrown as if something is pulling them. This centrifugal force is also occurring with the Earth rotating at a speed of approximately 1,675 kilometers per hour.
.
This force causes the material within the planet to swing outward around the equator. where is the length of the diameter at the equator. (from left to right) is equal to 12,756 kilometers, but the diameter from pole to pole (pole-to-pole diameter, top to bottom) is 12,714 kilometers, a difference of about 42 kilometers, and the faster the star spins, the more ‘bulging’ it will be.
.
The most obvious example is Saturn. It has a diameter of 120,500 km at the equator, but its diameter from pole to pole is 108,600 km, a difference of nearly 12,000 km.
.
“The rotation of the Earth creates a maximum external force at the equator and zero at the poles,” said Dr. Alastair Gunn, a radio astronomer from the University of Manchester. Writing on the BBC Science Focus website, “Because the Earth is not perfectly solid across the board, This force causes the Earth to be ‘squeezed’ into a slightly flattened sphere.”
.
Today scientists track the shape of the Earth using a combination of techniques to obtain the most accurate information. For example, there are thousands of Global Positioning System machines around the world that can measure changes in elevation up to a few millimetres. Including a method called ‘Satellite laser’ using ground stations to put lasers up to the satellite to measure changes.
.
These technologies have enabled modern humans to have clocks that always run on the clock, no matter where they are in the world. It also helps to determine the location or navigation more accurately.
Searched and edited by Witit Borompichaichartkul
Origin
