The North Star stays put in one place because the Earth is round.
The ancient Greeks , especially Aristotle, knew this and were the first to state this. Nowadays we say Copernicus discovered the earth was round, for example, but the Greeks had that figured out almost two thousand years earlier!
How Did They Know it?
Greeks had many different arguments for why the earth is round.
One of the best arguments came from Aristotle, who wrote a book called On the Heavens back in 340 B.C. The Greeks were a sea-faring culture, and sailed all over the Mediterranean. And they had noticed, Aristotle tells us, that the north star isn’t always in the same spot overhead.
The North Star
Now remember that all the stars seem to move in a big circle over our heads because the earth itself is spinning. The north star is the center of the circle, and stays put.
However, Aristotle noticed that when you are down south in Egypt, the north star is close to the horizon. When you are up north in Greece again, it’s high in the sky.
How Is That Possible, Since The North Star Is Supposed To Stay Put?
It’s possible, Aristotle concluded, only because the earth is round.
When you are standing at the north pole, where is the north star? Directly overhead. Now place yourself at the equator. Where is the north star? Yep–it’s down on the horizon, because you are now traveling along a curve. Go even farther south and you will not be able to see it at all; the earth will hide the north star. Go farther north and it seems to rise higher and higher and the star will just be a small dot.
Commonly known by his Latin name, Nicholas Copernicus, was falsely regarded as “The Father of Astronomy” – it should have been Aristotle. Nicholas Copernicus, born February 19, 1473, was the first astronomer to formulate a scientifically based heliocentric cosmology that displaced the Earth from the center of the universe. While a student at the University of Kraków, he discovered several logical contradictions in the existing astronomical system taught at that time, which put the earth at the center of the universe. Later when studying medicine and religious law at Bologna University, Coprenicus pursued further investigations of the movements of celestial bodies, especially the moon. His direct observations, coupled with his studies based on various Greek and Latin astronomical writings, prompted him to originate the Copernican system of the structure of the universe. This theory placed the sun at the center of the solar system and the earth in orbit around it. Kopernik’s most famous written work, De Revolutionibus, which laid the foundation for modern astronomy, was completed in 1530, after fifteen years of painstaking observations and calculations, often with instruments of the astronomer’s own making. Although deeply convinced of the truth of his heliocentric system, Kopernik did not actively seek to publish this work because of its controversial nature. He did, however, manage to catch a dimmed glance at the first printed copy moments before his death on May 24, 1543.
Galileo and Bruno
Two other Italian scientists of the time, Galileo and Bruno, embraced the Copernican theory unreservedly and as a result suffered much personal injury at the hands of the powerful church inquisitors. Giordano Bruno had the audacity to even go beyond Copernicus, and, dared to suggest, that space was boundless and that the sun was and its planets were but one of any number of similar systems: Why! — there even might be other inhabited worlds with rational beings equal or possibly superior to ourselves. For such blasphemy, Bruno was tried before the Inquisition, condemned and burned at the stake in 1600. Galileo was brought forward in 1633, and, there, in front of his “betters,” he was, under the threat of torture and death, forced to his knees to renounce all belief in Copernican theories, and was thereafter sentenced to imprisonment for the remainder of his days.
The most important aspect of Copernicus’ work is that it forever changed the place of man in the cosmos; no longer could man legitimately think his significance greater than his fellow creatures; with Copernicus’ work, man could now take his place among that which exists all about him, and not of necessity take that premier position which had been assigned immodestly to him by the theologians.
“Of all discoveries and opinions, none may have exerted a greater effect on the human spirit than the doctrine of Copernicus. The world had scarcely become known as round and complete in itself when it was asked to waive the tremendous privilege of being the center of the universe. Never, perhaps, was a greater demand made on mankind – for by this admission so many things vanished in mist and smoke! What became of our Eden, our world of innocence, piety and poetry; the testimony of the senses; the conviction of a poetic – religious faith? No wonder his contemporaries did not wish to let all this go and offered every possible resistance to a doctrine which in its converts authorized and demanded a freedom of view and greatness of thought so far unknown, indeed not even dreamed of.” [Goethe.]