Learn about the history of science by reading about the significant scientific events that took place on this day in history.
1997 - Kenneth Vivian Thimann died.Thimann was an English-American plant physiologist who isolated the plant growth hormone auxin. Auxin promotes cell elongation, formation of roots, and growth of buds in plants. Thimann's discovery led to the development of synthetic auxin to create products to functions ranging from root enhancers to weed killers.
1969 - Soviets perform first docking in space.Capsules from Soyuz 4 and Soyuz 5 met in orbit and connected to perform the first docking of spacecraft in space. The combined capsules were also called the first space station. They remained combined for three orbits and Soyuz 4 crew members transferred to the Soyuz 5 capsule. They became the first crew to return from orbit on a different spacecraft than from the one they launched into space.
1948 - Henri-Alexandre Deslandres died.
Bulletin de la société astronomique de France, 1913
Deslandres was a French astronomer who invented the spectroheliograph. This device allowed him to photograph the Sun in monochromatic light. He studied the solar chromosphere and solar activity. He also determined the rotation rates of the planets Jupiter, Saturn and Uranus.
1908 - Edward Teller was born.
Lawrence Livermore National Laboratory
Teller was a Hungarian-American physicist who was a central figure in the United States nuclear weapons program. During the Manhattan Project, he led the Los Alamos theoretical physics department. After the Soviets detonated their atomic bomb, his designs were used to build the hydrogen or thermonuclear bomb. He continued his strong defense policies as the director of the Lawrence Livermore Laboratory and was an outspoken proponent of the antiballistic missile programs.
1895 - Artturi Ilmari Virtanen was born.Virtanen was a Finnish biochemist who was awarded the 1945 Nobel Prize for his work and inventions in agricultural and nutrition chemistry. He developed a method to preserve grain silage by increasing the acidity of stored grains. The AIV (named after his initials) fodder technique is an additive that is sprayed on stored grains to raise the acidity of the grain to stop the fermentation that spoils the grain while in storage without destroying the nutritive value.
1785 - William Prout was born.
Henry Wyndham Phillips (1820 - 1868)
Prout was an English chemist and physician who investigated the chemistry of the stomach and urinary systems. He was the first to show gastric juice was hydrochloric acid. Prout was most famous for what became known as Prout's hypothesis. Based on the values of atomic weights of elements of the time, he believed all elements weights were integer multiples of the weight of hydrogen. This led to the idea that all elements were made up of condensed hydrogen atoms.