Logic will get you from A to B but Imagination will take you everywhere
For thousands of years, The Story of Humans and Space had been the story of staring out and wondering. The possibility of people leaving our Earth island and venturing out into space burst open the human spirit of adventure.
I imagine a similar feeling in the people of the 15th century, during the Age of Discovery, when we were working our way through the world map of Where Are We? and the notion of cross-ocean voyages dazzled people’s imaginations. If you asked a child in 1495 what they wanted to be when they grew up, “an ocean explorer” would probably have been a common response.
Questions for which we were trying to find the answers:
- What is the big thing in which we are staying????
- Who has put us in here??????
- Where do the dead people go???
- Is there any life other than ours in the universe????
So let us try to decipher the code and answer the same using explanations that has been proposed long back in history and the present condition. Since the answers are too long I will try to answer it in different parts so let me try to give an idea how people in 15th century tried to decipher it:
So first thing that comes to mind is Astronomy, if you google it then the dictionary definition for Astronomy is-
“The study of objects and matter outside the Earth’s atmosphere and of their physical and chemical properties”.
So according to definition astronomy is the study of physical and chemical properties of object outside the Earth atmosphere, but what about Earth there will be some person in history who has studied about Earth dimensions (After understanding Earth is not flat).So let talk about our first lead who was very close to give the circumference of earth and how he did it.
So our first hero is Eratosthenes, he was a Greek astronomer:
His role in history was how to find the circumference of earth??????????????????, how will he find the diameter of the earth that I can just google and found.
Method used to measure the Circumference:
Eratosthenes used the lengths of shadows to figure out how high in the sky the Sun was in a certain place (Place 1) on a certain day. He knew of another place (Place 2) where there was no shadow at all on the same day. That meant the Sun was straight overhead. He found out the distance between the two places, then used some geometry to figure out the rest. Confused……………
Let’s take a closer look! Eratosthenes lived in the city of Alexandria (Place 1). Alexandria is in northern Egypt. It is by the Nile River and the Mediterranean Sea. There was a tall tower in Alexandria. Eratosthenes measured the length of the tower’s shadow on the summer solstice. He used that information plus some geometry to figure out the angle between the Sun and straight up. There was a town in southern Egypt called Syene (Place 2). There was a well in Syene. On the Summer Solstice, the Sun shone straight down the well to the very bottom. That meant the Sun must be straight overhead.
Eratosthenes had someone measure the distance between Alexandria and Syene. He used that distance, what he knew about the Sun’s angles, and a bit of geometry to figure out the size of the Earth.
Pictorial representation of the same:
The distance between Alexandria and Syene was measured in stadia. The stadion was a distance unit that was often used in ancient times. However, not everybody used a stadion of the same length. The Earth is about 40 thousand kilometres (about 24,860 miles) around and that is very close to what I found out via Google – 40,075 km.
For more detail explanation please go through the video – https://vimeo.com/84594487
Now time to go back, how the hell he came to Know about earth, other planets so our wild entry person Claudius Ptolemy, comes in to picture he is the author of Almagest, the book which was referred for Astronomy till 14th century(Even though it was wrong).
According to him, “The earth does not rotate, otherwise objects will fling off its surface like mud from a spinning wheel. It remains at the centre of things because this is its natural place-it has no tendency to move one way or the other. Around it the larger spheres move”.
If you have watched Pirates of Caribbean, there is a famous dialogue by Governor Swann – “Even a good decision if made for the wrong reasons can be a bad decision”. So till 14th century everyone use to think that earth is at the centre and then our main lead came in to picture, who is none other than Nicolaus Copernicus(1473-1543)
He stated, “The sun is at the centre of the solar system, and planets orbit around it in perfect circles”. Not only he placed the sun at the centre of the solar system, he also gave detailed account of Earth, moon, planets. He said that earth rotate around its axis which accounts for days and nights.
Religious leaders of his time were against him calling him as “A new astrologer …………. The fool”, who wanted to overturn the entire science of astronomy. But he was the one who has provided us the true knowledge of astronomy and all the works till date that has been performed is directly or indirectly related to this person.
Star of Bethlehem
In Christian tradition, the Star of Bethlehem, also called the Christmas Star, revealed the birth of Jesus to the Biblical magi, and later led them to Bethlehem. The star appears only in the native story of the Gospel of Matthew, where astrologers from the east are inspired by the star to travel to Jerusalem. There they meet King Herod of Judea, and ask where the king of the jews had been born.
Now the question is why suddenly I brought Christianity while we were discussing about Humans and Space, the reason is for bringing in our next important person Johannes Kepler (1571-1630) ,you may have surely heard about this guy because he was there in your school books as “Three laws of Planetary motion”.
So now the answer for the question why star of Bethlehem – In December 1603, Kepler was intrigued by the planetary conjunction of Jupiter and Saturn, he began computing the planetary positions at the time of the birth of the Jesus. His calculation showed that there was a triple planetary conjunction of Jupiter and Saturn in 7 BC on 27 May, 5 October and 1 December. Now he is the person who stated laws for planets and on basis of his study Galileo confirmed physically the existence of sun centred solar system (Discussed later in part1).
Kepler’s laws of planetary motion:
- First Law: The path of the planets about the sun is elliptical in shape, with the centre of the sun being located at one focus. (The Law of Ellipses).
- Second Law: An imaginary line drawn from the centre of the sun to the centre of the planet will sweep out equal areas in equal intervals of time. (The Law of Equal Areas).
- Third Law: The ratio of the squares of the periods of any two planets is equal to the ratio of the cubes of their average distances from the sun. (The Law of Harmonies)
He is also the author of Somnium (Fiction) in which he dreamed of building a ship to sail the oceans of space in the universe.
Now our last hero for part 1 Galileo Galilei (1564-1642), this guy had very sad ending.
Galileo confirmed and advanced Copernicus sun centered system by observing the skies through his refracting telescope, which he constructed in 1609.His theories were thought to contravene the teachings of the Catholic Church, in 1633 he was tried for heresy by the inquisition and force to renounce his theories. Tradition has it that he was so convinced that it is the earth that moves that the moment he was released after recanting his belief in the Copernican system, Galileo stamped his foot and muttered “E pur si muove” (And yet it moves).
So far I have tried to explain about the progress in astronomy till 15th century, in part 2 I will try to explain the technology advancement in 19th and 20th century.