Learn about the history of science by reading about the significant scientific events that took place on this day in history.
1822 - Louis Pasteur was born.
Pasteur was a French chemist and microbiologist who discovered with Claude Bernard a method to slow the development of microbes in milk and wine called pasteurization. The process involves heating the liquid just high enough to kill any microbial life without spoiling the product. He also created the first vaccine against rabies.
1571 - Johannes Kepler was born.
Kepler was a German mathematician and astronomer who outlined the Kepler three laws of planetary motion. The first law says planets have elliptical orbits with the Sun at a focus. The second states a line joining the Sun and the planet sweeps out an equal area during an equal amount of time and the third law relates the orbital period of a planet and the semi-major axis of its orbit. These laws were instrumental in Newton's theory of gravitation.
1914 - Charles Martin Hall died.
Hall was an American chemist who discovered an inexpensive method to refine aluminum from ore. He built an apparatus that passed an alternating electrical current through a solution of alumina and cryolite that would cause aluminum metal to precipitate out. This process was also discovered by French chemist, Paul-Louis-Toussaint Héroult at nearly the same time and is generally known as the Hall-Héroult process. It was responsible for greatly reducing the cost to produce aluminum and made it one of the most widely used metals today.