History of Cosmology

Newton creates first dynamical theory of gravity

Jul 5, 1687

Source 2In his book Principia Mathematica, Newton outlines his 3 laws and explains what he has theorised about gravity.
Source 1

Herschel

Jan 1, 1785

• Discovered Uranus
• Theory of Evolution of Stars
• Theory of the structure of nebulae

Laplace

Jan 1, 1799

• Made astronomy more mathematical
• Theory of probabiltiy
• Theory of sound
• Wave theory
• Black holes and gravitational collapse

Lowell

Jan 1, 1895

• Studied Mars
• Theorised about intelligent life on Mars
• Predicted Pluto

Einstein

Jan 1, 1905

• Photoelectric effect (proves light is wave and particle)
• Theory of Relativity (speed of something depends on speed and difference in speed)

Leavitt

Jan 1, 1908

• Discovered over 1200 stars
• Discovered relationship between luminosity and period of Cepheid stars

Hubble

Jan 1, 1920

• Discovered that galaxies move away from us at a speed proportional to distance
• Expanding Universe

Lemaitre

Jan 1, 1927

• Created Big Bang Theory
• Researched cosmic rays
• Researched three-body problem
• Source: http://www.britannica.com/biography/Georges-Lemaitre, 1/5/16

De Sitter

Jan 1, 1932

• Worked with Einstein
• De Sitter Space

Hoyle

Jan 1, 1946

• Stellar nucleosynthesis
• Critic of scientific theories including the Big Bang Theory

Shapley

Jan 1, 1953

• Estimated size of Milky Way
• Liquid water belt theory (habitable zone)
• Great debate about spiral nebulae and size of universe (Curtis)

Penzias and Wilson

Jan 1, 1964

• Discovered cosmic microwave background radiation
• Evidence for Big Bang Theory