Timeline of Scientists that contributed to cosmology By JT (Jack) Period: 1500 to 2020 Cosmology 1543 Nicolaus Copernicus 1600 Tycho Brahe 1609 Johannes Kepler 1687 Issac newton 1773 Pierre-simon Laplace 1781 William Herschel 1894 Percival Lowell Founded Lowell Observatory in Flagstaff which led to the discovery of Pluto 1896 Henrietta Leavitt 2,400 variable stars between 1907 and 1921 1898 Willem de Sitter 1905 Albert Einstein 1924 Harlow Shapley 1927 Georges Lemaître 1929 Edwin Hubble 1946 Fred Hoyle 1964 Arno Penzias and Robert Wilson 1964 Arno Penzias and Robert Wilson