Famous Dead Guy timeline.

101

Thales. 620 BCE

investigated basic principles of atoms
Period: 101 to Oct 4, 1932

Fam. Dead Guy
102

Democritus. 440 BCE

first atomic theory
103

Aristotle. 340 BCE

believed that everything was made up of fire, Earth, water, and air
104

Sir Issac Newton

believed that solid matter is formed of solid, massy, impenatrable particles
Oct 4, 1803

Dalton

came up with the first atomic theory
Oct 4, 1896

Becquerel

discovered radioactivity
Oct 4, 1897

JJ Thompson

discovered electrons
Oct 4, 1908

Millikan

found charges in electrons
Oct 4, 1910

Gold Foil Experiment

Alpha particles were fired through a thin slice of gold into large angles.
Oct 4, 1911

Rutherford

discovered nucleus and protons
Oct 4, 1913

Bohr

discovered that electrons had orbits.
Oct 4, 1919

Aston

identified isotopes, and invented mass spectograph
Oct 4, 1926

Schrodinger

used math equations to find the probability an electron would be in a certain position
Oct 4, 1932

Chadwick

discovered Neutron

Thales. 620 BCE