1944 - Charles Barkla died.

Nobel Prize Foundation

Barkla was an English physicist who was awarded the 1917 Nobel Prize in Physics for his research on x-ray transmission though matter. He found that each element had its own characteristic x-ray spectra.

1920 - Tetsuya Theodore "Ted" Fujita was born.

NOAA

Fujita was a Japanese-American meteorologist who studied severe storm systems. He is best known for his Fujita scale to rate the severity of tornadoes. This scale measures tornado intensity and relates wind speed to the amount of damage the tornado causes. He is also known for the discovery of microbursts. These powerful, short-lived bursts of air are caused by a downdraft of air that pushes outward at the ground level.

1908 - Ilya Mikhaylovich Frank was born.

Idaho National Labs/DOE

Frank was a Soviet physicist and shared the 1958 Nobel Prize in Physics with Pavel A. Cherenkov and Igor Y. Tamm for the discovery and theoretical explanation of cherenkov radiation. Cherenkov radiation has a distinctive blue glow and is formed with charged particles pass through a medium where the speed of light is less than the speed the particles are moving. This discovery opened new methods of measuring the speed of relativistic particles in nuclear physics.

1905 - Felix Bloch was born.

Stanford University / Courtesy Stanford News Service

Bloch was a Swiss physicist who shares the 1952 Nobel Prize in Physics with Edward Mills Purcell for their independent discovery of nuclear magnetic resonance (NMR). Bloch discovered NMR while investigating the magnetic properties of atomic nuclei. He also served as the first director of the European high-energy laboratory, CERN.

1875 - Gilbert Newton Lewis was born.

Lawrence Berkeley National Laboratory

Lewis was an American chemist who discovered the produced the valence bond theory and introduced Lewis dot structures to chemistry. He also postulated the electron pair relationship of acids and bases that is known as the Lewis theory of acids and bases. He produced the first samples of deuterium and isolated heavy water.