flat earth it concerns a set of ideas defended by people who believe that the Earth be shaped like a plane, bounded by the Arctic Circle, not a sphere. some of the calls earth planners they also believe that the gravity it is a hoax and that the Moon and Sun are much closer to Earth than is believed.
If you still have any doubts about the shape of the planet, it's important to know the scientific discoveries that attest to its sphericity. Come on?
Read too: Myths and truths about the arrival of man on the moon
What do those who believe the Earth is flat say?
flat earth is an archaic conception that assumes the Earth is shaped like a flat disc. Many cultures and ancient scholars, lacking in astronomical technologies and knowledge, believed in this model. philosophers as tales, Leucipus and Democritus imagined that the Earth was flat, but names like Pythagoras and Aristotle already believed in the spherical shape of our planet.
In recent times, it is increasingly common to hear about people who believe the Earth is flat. However, all the scientific knowledge accumulated over the centuries indicates that the Earth is spherical.
Earthmen generally base their arguments on simplistic empirical observations, such as the fact that we can't see the curvatureofhorizon. However, this reveals the ignorance of the notion of referential, which explains why the Earth's curvature is imperceptible to an observer close to the ground. Furthermore, they discard photographic evidence, scientific experiments, space expeditions, astronomical observations, the existence of gravity, meteorological phenomena, etc.
Although there is no consensus among the earth leveling believers themselves about the flat earth features, since there are several different speculations among them, we can present some of the common points defended by many of them.
Most earth planners claim that the continents are arranged around the North Pole and that the entire Southern Hemisphere is spread over the outer circumference of a circular plane. They also defend the non-existence of Antarctica as we know it. From a terraplanist point of view, the frozen continent is actually a large wall of ice that stretches over the edges of the Earth (although this is not a consent among all earth planners).
Furthermore, they claim that the Moon and Sun are relatively close to Earth and they circle around the North Pole in a plane parallel to the surface, propelled by some kind of unknown force, since, as we said, many earthmen deny the existence of gravity – for them, the entire Earth develops an ascending and accelerated movement at a rate of 9.8 m/s², as if we were in an elevator that goes up accelerated. That's why we feel stuck to the ground.
One of the arguments used by the earth planners to deny gravity is that it is strong enough to keep buildings anchored to the ground, while it is weak enough to allow birds, for example, to be able to fly freely. However, this type of statement demonstrates a clear lack of knowledge about the concepts of inertia and acceleration.
It is worth saying that the earth plane view it cannot explain, for example, why we see farther when we stand at ever greater heights. Furthermore, there would be no reason why we could not visualize a good part of the rest of the world if everything were contained in the same plane.
Read too:Why hasn't man returned to the moon yet?
Earth shape throughout history
Many were the scholars, scientists and philosophers who carried out experiments and observations to identify what the real Earth geometry would be. Aristotle, for example, even made observations that supported his arguments that the Earth was spherical. At the time, his conclusion was that the only possible shape for the Earth was the curved.
Furthermore, many observers throughout history were able to perceive that some constellations were only visible from certain points on Earth (the North Star, for example, can only be seen from the Northern Hemisphere) and also that, when they moved away from the horizon, the boats gradually disappeared, showing their masts and sails before disappearing by complete.
Scientific discoveries that refute the concept of flat earth
→ Eratosthenes and the circumference of the Earth
THE Earth circumference was estimated by Aristotle, however the first faithful measure was performed by Eratosthenes in 240 BC Ç. For this purpose, Eratosthenes drew on knowledge of geometry inherited from the Pythagoreans and the astronomy of the time. He figured he could calculate the Earth's radius if he were able to measure the distance between two cities 800 km distant - Alexandria and Siena –, also measuring the size of the shadow of a stick positioned in these two places, on the same day of the year.
The date chosen for the measure was not random. Eratosthenes waited for the solar zenith in Siena, that is, in that region, the rays of light fell perpendicularly to the ground, so that the rod used in Siena did not cast a shadow. With that, he was able to measure the angle of inclination between the rods placed in the cities of Alexandria and Siena, obtaining an angle of approximately 7 degrees.
Based on this, he determined that 360 degrees would be approximately 50 times the distance between these cities and thus inferred that the terrestrial circumference would be approximately 40,000 km. Even with such simple methods, Eratosthenes achieved an incredible result. 5% deviation in relation to the measurements currently made with the help of satellites.
→ Foucault's Pendulum and the Earth's Rotation Motion
In 1851, the French physicist Jean Bernard Léon Foucault he developed an experiment to demonstrate that the Earth rotated on its own axis. The experiment consisted of placing a large mass hanging from a 67 meter wire to oscillate in a large amplitude.
THE centripetal acceleration produced by Earth rotation causes the pendulum to have its plane of oscillation affected. Through this experiment, it was possible to determine the coordinates of latitude and longitude without any kind of external observation.
THE acceleration that affects the plane of oscillation of the pendulum is called Coriolis acceleration. Despite being very low compared to gravity, it interferes with the movement of the oceans and the formation of Ocean currents.
See too:PWhy don't we feel the Earth rotate?
→ Euclidean geometry and the shortest distance between two points
Around 300 BC C., the mathematician Euclid developed the geometryEuclidean. According to her, the shortest distance between two points in the surfacesspherical is not a straight, but yes a arc of circumference, which nowadays we call orthodromy.
Let's apply this to the present, for example: if a plane leaves São Paulo towards Paris traveling online straight (this line is called loxodromia), it will travel a greater distance than if it followed the curvature of the Earth. This would not happen if the Earth had a flat geometry. It is based on this that the routes of the navigations and also the long-haul flights.
→ Claudio Ptolemy and the maps of the terrestrial globe
A few centuries after Euclid, around 150 AD. C., the astronomer Claudio Ptolemy wrote a treatise called geography based on the circumference of the Earth estimated by Eratosthenes and on the geometry of Euclid, thus creating a system of coordinates based on latitudes and longitudes, which is still used today in location systems and also in navigations.
Lookalso: History of Astronomy – the timeline of major astronomical discoveries
→ Circum-navigations
The evolution of maps allowed the realization of circumnavigations, which are nothing more than turns around a region. In this case, we are talking about turns around the Earth itself. Ferdinand Magellan, for example, was known for performing the first successful circumnavigation in history, traveling constantly along a single direction and thus returning to the point of origin.
THE Earth curvature also explains why we use the meridians and the time zones. Since the sun rises in the east and sets in the west, different parts of the globe receive different levels of luminosity, thus promoting the separation between day and night.
→ Newton's gravitation and the shape of the Earth
From thethistory of gravitation universal, the english physicist Isaac Newton showed that it was possible to calculate the intensity and direction of the attractive force that a pasta exercised over another. Calculations made by Newton allowed to predict the trajectory of asterOyou go and even the formation of the tides, in addition to providing an explanation for the shape of the Earth and other planets.
According to the theory of gravitation, the gravity it makes large clumps of mass attract each other equally along all directions. In this way, matter tends to occupy smaller and smaller spaces, whose radius, with the passage of time, tends to be equal in all directions. The only format that admits such a condition is the spherical.
Furthermore, according to the calculation and based on gravitationuniversal, both developed by Newton, if the Earth were flat, the gravitational force would increase as we approached your edge. At these points, contour effects would cause gravity to point in an almost parallelto theground, if so, we would end up "falling" back to the center of the Earth. In this way, there would be no way for there to be anything in the boundary zones of a flat planet, not even the polar layers, which, according to the terraplanist view, surround the Earth.
See too: Lhere is Newon - the laws that determine the dynamics of the movement of bodies
→ Einstein's General Relativity and the shape of the Earth
at the beginning of 20th century, Albert Einstein proposed to theory ofThe relativity special and The of general relativity. The latter establishes the relationship between the path taken by light and the gravitational field. According to the general relativity, at electromagnetic waves their trajectory is altered by the presence of massive bodies, such as stars and planets. This phenomenon has been tested and proven many times.
In one of them, two atomic clocks were synchronized so that a difference of 1 second between them would only be observed if several billions of years. Then, one of these clocks was placed on an airplane that was moving at high speed and at a great height above the ground, where the other clock was left. When the plane landed, a considerable difference was measured in the recordings of the two clocks, indicating the influence of gravity on the passage of time.
Technologies like the GPS are used to determine our position on the globe by measuring the time that a radio wave it takes to reach us and return to the issuing source. Therefore, for us to use this type of technology, it was necessary for the fieldgravitational of the Earth (which depends on its shape) was taken into account and that some correctionsrelativistic were applied, otherwise we would never be able to measure positions remotely with such precision.
See too:7 questions still unanswered by Physics
I have my doubts, now what?
in front of all the scientific knowledge accumulated by humanity throughout history, admitting that the Earth's shape is flat is the same as give up fundamental concepts of Science that are the basis of several technologies present in our daily lives and that have shaped our lifestyle over time. However, there is no problem with to doubt or to question things, however established they are, as it is also Science's role to produce new questions.
If you still have your doubts, try to solve them based on a rational structure of scientific investigation – watch, make questionspertinent, formulatehypotheses,performexperiments or yet searchto know if someone has already done them, so that you may or may not reach a conclusion. And even if that doesn't happen, there's no problem, after all, scientists experiment without worrying about what they'll find in the end – scientific discoveries come along the way.
Remember: when browsing the internet, always be wary of sensationalist publications and from videos or posts made by people other than authoritiesscientific and academics. In doubt, look forOyourteacher.
By Rafael Hellerbrock
Physics teacher