ancient astronemer timeline

Eratosthenes

240 BCE

Eratosthenes was the first to believe that the earth is round he used the sun to measure the earth his measurement was 39690 km he measuring helped people to believe that the earth is round

Claudius ptolemy

150 BCE

in ancient greece ptolemy made a model of the solar system with everything revolving around earth even though it was wrong it would inspire astronomers to create their own theories about the universe

nicolaus copernicus

1543

copernicus published his book de revolutionibus orbium coalestium which helped explain his theory on the earth revolving around the sun this book help his ideas gain credence

Johannes kepler

1605

Johannes Kepler created the 3 laws of planetary motion
1.each planets orbit is around the sun is an ellipse
2.in their orbits around the sun the planets sweep out equal areas in equal time
3.the squares of the times to complete one orbit are propotional to the cubes of the average distances from the sun
these laws helped us to understand the moving cycle of the planets

Isaac newton

1686

Isaac newton made his 3 laws called newtons laws
1.objects at rest stay at rest & objects in motion stay in motion
2.objects will maintain their motion until a force is applied
3.each force has an equal and opposite force
these laws help us understand motion

Albert einstein

1905

Einstein had many theories that the law of physics is the same everywhere In the universe the speed of light in the vacuum is constant and space and time are linked by an entity called space time
einstein was one of the greatest scientist of all time and his theories have helped us learn about the universe