Why are world globes important
World globes are the most accurate maps. The reason for this is very simple, Earth is a sphere, so is a globe. For this reason when you look at a world globe you can truly see the way the world looks in all of its simplicities and complexities.
All countries are shown in their true sizes relative to each other. There is no direction distortion so the distances between cities can be calculated, also a globe can be used to calculate the current time in each place in the world.
It has already been said that globes are much more accurate than any flat map. Imagine that the worlds surface is like an orange, peeling off the skin and laying it flat would leave lots of gaps. How to accurately reproduce a globe onto a flat map surface is what cartographers have been trying to do for at least 400 years. On many world maps, countries appear distorted, especially those far away from the equator. Greenland might appear bigger than Africa for example when it is 4 x smaller.
Flat world maps do have their uses though, after all you can't fold up a globe and put it in your pocket when travelling. Maps are particularly useful when used as objects to help find your way around a city for example. When a map is confined to such a small area, any distortions or other problems that occur at a world level are minimal but when looking at the whole world a globe is clearly a more accurate and more attractive choice.
Early opinions on the Earth's shape
When astronauts look down at the Earth from space, all they see is a huge blue and white sphere. Clearly thousands of years ago humans did not have the ability to pop into space to see what the world looks like.
It must have been very hard to imagine the shape of the world hundreds of years ago as must of the world, as far as the eye can see seems almost totally flat. Its really no surprise that many people believed the world to be a flat disc, also as many early sailors who sought to explore never returned you might imagine that it is quite easy to come to the conclusion that they may have simply fallen of the edge of the Earth.
In Greece, storytellers used to describe the world as a flat disc, surrounded by the "Ocean River". Hundreds of years later, Aztecs had a similar idea about the world. They believed that the world was a flat disc with a great circle of water around it.
Some had the right idea
Even thousands of years ago people were finding wholes in the argument of a flat world. If it was true that the world was flat then why did the sun rise in the east and set in the west every day? Why did the stars move in circles in the nights sky? These observations didn't prove that the world was round but they did give vital clues as to the true shape of the Earth.
Many myths trying to explain motions of the sun were created by various religions. For example the story of the chariot pulling the sun across the sky each day. Such stories were quite persuasive but little by little more and more people came to believe that the Earth must be a sphere.
The truth emerges
At around 250BC, the Green mathematician Eratosthenes noticed that a post in the city of Alexandria, Egypt cast a shadow at noon on the summer solstice, the longest day of the year. At the same time in Syrene, a town due south from Alexandria at an angle. This was because the Earth's surface was curved, Eratosthenes reasoned.
By knowing the distance between the two cities and by calculating the angle of the pole to the shadow. Eratosthenes was able to apply geometric theory to determine the diameter of the world to an impressive accuracy. He calculated that the world was 7850 miles in diameter when it is 7926 miles in diameter at the equator.
Though Eratosthenes argument was very impressive and seemed to be irrefutable it must have been to complicated a reasoning to persuade the massive majority of people to come over to the correct way of thinking.
Where did the Earth fit into the universe?
By around 150BC most Greeks had accepted that the Earth was a globe, sphere shaped.
There was still a problem in that they did not know how this world globe fitted into the universe. Aristarchus, who lived in the 200s BC said correctly that the Earth revolved around the sun, but not many people believed him. Instead, they believed Claudius Ptolemy, an astronomer who said the moon, the sun, the planets and stars revolved around the Earth in a series of circles. For another 1400 years this mistaken idea was believed and accepted by the wider community.
In 140BC, a Greek man known as Crates of Mallus built what may have been the first globe in history. It is difficult to picture what this globe must have looked like as the Greeks had not explored Australia, the Americas not the mention the poles.
What were the Chinese thinking?
In China at around the same time as the Greeks, some Chinese astronomers thought the Earth was a hemisphere-like globe sliced in half underneath a dome shaped universe.
Other Chinese thinkers thought the universe like an egg, with the earth as the yolk. Then there was a third group of Chinese astronomers who said the universe was an infinitely large, almost empty space, where spheres like the sun, the moon and the Earth floated around very very far way from each other. This is very close but like the Greeks, the Chinese dropped this idea and stuck with the theory of the egg-shaped universe.
What were the Arabs thinking?
Astronomers in India learned about the universe by reading books written by the Greeks. Around 500AD, an Indian astronomer Aryabhata explained why the stars circled the Earth in the night sky. He believed the Earth must be spinning like a top.
The Arabs learned about astronomy from previous cultures, the Chinese and Greeks. They also used shadows to predict the diameter of the Earth. In the 1300's a former slave called al-Khazini came up with the idea of gravity, he stated that everything was attracted to the centre of the Earth.
Finally getting rid of old myths
Before European explorers and conquerors sailed across the oceans in the 1400s and 1500s, cartographers in Europe made globes. In 1492, Martin Behaim, a German cartographer, made the oldest globe that still exists today. Years later, the Dutch would become famous across Europe for striving to create the highest quality, most detailed globes of the time.
The problem was that even up to the 1600s people in power would still believe that the Earth was the centre of the universe. I real push began by educated people to persuade people against this way of thinking. Polish astronomer Nicolaus Copernicus, German astronomer Johannes Kepler and Italian astronomer Galileo Galilei proved that all views about the Earth being the centre of the universe were nonsense. They showed conclusively that the Earth orbited the sun. Many religious leaders refused to believe these new ideas, the pope famously persecuted Galileo and the books of Copernicus were banned.
Finally in Sir Isaac Newton there was a man powerful enough and respected enough to force the issue. Isaac came up with the first theory that explained the movements of the sun, the moon and the planets. Newton realized the force that causes an apple to fall from a tree was also the force that kept the moon in orbit around the Earth. Newton explained that this force called gravity held the solar system together. Today, scientists are still getting more information about the universe and the laws of physics, but Newton's laws of motion give a pretty good description of everything that happens around us to this day.
Thanks to Replogle World Globes for this text.
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