Atomic Theory TImeline

Democritus

400 BCE

Birth-Death Date: 460-370 B.C.E
Summery: Democritus was a Greek philosopher who established the idea of the atom and that it is the basic building block of matter. He believed that atoms were solid particles that are tiny, uncuttable, and surrounded by empty space. Democritus also thought they constantly move at random.
Fact: After his father had died Democritus being a wealthy heir spent his inheritance on travelling all around the world learning from other scholars.

John Dalton FRS

1803

Birth/Death Date: Sep 6, 1766 - July 27, 1844
Summary: John Dalton was an English scientist who discovered that oxygen combined with either one or two volumes of nitric oxide in closed vessels over water. His observations provided important experimental evidence for atomic ideas in general.
Fact: John was actually color blind and inspired by this. He performed the first research into color blindness.

Joseph John Thomson

1897

Birth-Death Date: Dec. 18, 1856 - Aug. 30, 1940
Summary: Joseph Thomson was a British scientist who designed and performed a series of experiments that was also being investigated by many scientists at this time. The study was the nature of electric discharge in a high vacuum cathode-ray tube.
Fact: JJ Thomson was a recipient of the Order of Merit and he was knighted in 1908

Robert Andrews Milikan

1910

Birth/Death Date: March 22, 1868 - Dec. 19, 1953
Summary: Robert Milikan was a physicist who discovered the elementary charge of an electron using the oil drop experiment.
Fact: Robert was not only a scientist but also an athlete he played tennis and golf.

Ernest, Baron Rutherford of Nelson

1911

Birth/Death Date: Aug. 30, 1871 - Oct. 19, 1937
Summary: Ernest Rutherford was a British scientist who established a nuclear theory with gold foil. He shot a beam of alpha particles at a sheet of gold foil, and some particles were deflected. He decided that a tiny, dense nucleus was causing the deflections.

Fact: In 1896 radioactivity was discovered 3 years later Ernest showed that there is at least two different types of radiation: alpha radiation and beta radiation.

Niels Henrik David Bohr

1913

Birth/Death Date: Oct. 7, 1885 - Nov. 18, 1962
Summary: Niels Bohr was one of the most foremost scientist of his time. He was known for his investigation into the measurements of liquid surface tension using oscillating fluid jets.
Fact: Niels Bohr and Albert Einstein won a noble prize at the same time in 1922.

Werner Karl Heisenberg

1925

Birth/Death Date: Dec. 5, 1901 - Feb. 1, 1976
Summary: Werner conducted an experiment considering trying to measure the position of an electron with a gamma ray microscope. He thought the high energy photo used to illuminate the electron would charge it's momentum in a certain way.
Fact: Werner met Niels Bohr in Copenhagen where they discussed a German project.

Erwin Rudolf Josef Alexander Schrödinger

1926

Birth/Death Date: Aug. 12, 1887 - Jan. 4, 1961
Summary: Erwin was a physicist who conducted ground breaking work in quantum mechanics. He developed a equation that predicted where an electron would be located in an atom.
Fact: Erwin has a crater on the moon named after him it is on the dark side of the moon, and it is called "large crater Schrodinger".

Sir James Chadwick

1932

Birth/Death Date: Oct. 20, 1891 - July 24, 1947
Summary: James Chadwick was a scientist who conducted an experiment which he infused Beryllium with alpha particles from the natural radioactive decay of Polonium. The results showed high penetration through a lead shield, and this could not be explained in this time period.
Fact: James graduated in 1911 when he graduated he received first class honors.