There are many famous astronomers but these six have greatly advanced the idea of space time. These astronomers were all very celebrated but only a few are extremely well known. The six astronomers and scientists, Joseph-Louis Lagrange, Johannes Kepler, Albert Einstein, Aristarchus of Samos, Isaac Newton and Claudius Ptolemy did much to invent and change the idea of space time curvature. I will give a brief explanation of their lives and what they did for space time.

Joseph-Louis Lagrange

1736 – 1813

Joseph-Louis Lagrange was an Italian mathematician though many people think of him as French. He excelled in all fields of analysis, number theory and celestial mechanics. In 1574 his first mathematical paper was published. This paper was actually a letter written to Giulio Fagnano about the binomial theory. Later in his life he began to study the use of differential equations. One of the ways he applied this was the orbits of the planets. A differential equation is an equation where you solve for a variable in an equation you know will give the answer.

Albert Einstein

1879 – 1955

Albert Einstein was a celebrated German mathematician who primarily worked on his theory of relativity. Another one of his hypothesis was that the speed of light remains the same in all frames of reference (air, water ect.). He also made contributions to the quantum theory. The theory of relativity as presented by Einstein said that space was curved by gravity and not just flat (space-time curvature). He said it was curved by gravity and without the curvature we would drift into space.

Aristarchus of Samos

310bca (Before Common Era) – 230bca

Aristarchus of Samos was a Greek mathematician who pioneered the attempts to figure out the size and distance of both the moon and the sun. He was inspired by the theory that we have a sun centered solar system and universe. He was not referred to in many mathematics books because he was an astronomer and therefore did not get the publicity that he had wanted for his work.

Johannes Kepler

1571 – 1630

Johannes Kepler was a German mathematician and astronomer that discovered that the planets travel in elliptical orbits instead of circular. He also gave us three laws of planetary motion. The first law states that that the sun is not at the center of an ellipse but at one of the focus points. The second law states that if a planet is closer to the sun it moves faster. The third law states that the further away from the sun you are the longer it takes to go around the sun.

Claudius Ptolemy

85AD – 165AD

Claudius Ptolemy was a very influential astronomer and geographer during his life from 85AD to 165AD. Not much was known about his life but he made most of his observations from 127AD to 141AD.  He created the geocentric theory which states that the earth is the center of the universe and everything orbits around it countering Aristarchus heliocentric theory. The heliocentric theory states that the earth and all the planets revolve around the sun.

Sr. Isaac Newton

1643 – 1727

Isaac Newton was a pioneering mathematician who is famous for his discoveries. In astronomy, he was the person who discovered how gravitation affects the planets journey around the sun. He discovered because of gravity from the sun influences the earth which is moving at high speeds. The earth gets swung around because of centrifugal force. Centrifugal force acts if something is swung around and pulls on it though it tries to escape. This is why the earth orbits and does not fly into the sun or fly into space. Now we know better that it is a gravitational attraction.