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Period: 276 BCE to 194 BCE
Eratosthenes
Used the Sun to measure the size of the round Earth. -
Period: 85 BCE to 165 BCE
Claudius Ptolemy
He made a model of the solar system in which the sun, stars and other planets revolved around Earth. Known as the Ptolemaic System. -
Period: Feb 19, 1473 to May 24, 1543
Nicolaus Copernicus
In the 16th century he composed a model of the solar system that involved the Earth revolving around the sun. He was 70 and dying, when his work was stolen by Kepler. In 1632 the Polish astronomers work cemented the Copernicus revolution. -
Period: Dec 14, 1546 to
Tycho Brahe
He dedicated his life to recording planetary positions ten times more accurately than the best previous work. Tycho built vast instruments to set accurate sights on the stars, and used multiple clocks and timekeepers. He achieved his goal of measuring to one minute arc. -
Period: Dec 27, 1571 to
Johannes Kepler
He believed God must have had some geometric reason for pacing the six planets at particular distances from the sun. Kepler found his three laws of planetary: First one was the planets move in elliptical orbits with the sun at focus.; Second one is In their orbits around the sun, the planets sweep out equal areas in equal times.;Third one is The squares of the times to complete one orbit are proportional to the cubes of the average distances from the sun. -
Period: to
Sir Isaac Newton
Is famous for his work on forces, specifically gravity. Newton's Laws of Motion: First one is an object at rest tends to stay at rest, Second one is the net force on an object is equal to the rate of change of its linear momentum, Third one is for every action there is an equal or opposite action. -
Period: to
Albert Einstein
In the 20th century he was the most famous scientist ever, after proposing a new way of looking at the universe that went beyond current understanding. That the laws of physics are the same throughout the universe.That the speed of light in a vacuum is constant and that space and time are linked in an entity known as space time, which is distorted by gravity.