July 2 in Physics History - Births – Physicists born on July 2
Hugh L. Dryden (2 Jul 1898 - 2 Dec 1965)
He was an American physicist and deputy administrator of NASA for 7 years who studied the aerodynamics of high speed. He headed the National Defence Research Committee during WWII. It developed the first successful US missile, the Bat radar-homing missile.
Hans Albrecht Bethe (2 Jul 1906 - 6 Mar 2005)
He was a German-American physicist who helped to shape classical physics into quantum physics. He also increased the understanding of the atomic processes responsible for the properties of matter and of the forces governing the structures of atomic nuclei. He studies nuclear reactions and reaction cross-sections. In 1943, he was asked to be the head of the Theoretical Division at Los Alamos on the Manhattan Project. He also received the Noble prize for physics (1967) for his work on the production of energy in stars.
Francis Simon (2 Jul 1893 - 31 Oct 1956)
He was a German-British physicist who worked on lowering temperatures below the point previously done by the Joule-Thomson effect. His work reached a low of 20 millionths of a degree above absolute zero. He used paramagnetic molecules at low temperatures and allowed their orientation to randomize. It abstracted the further heat and lowered the temperature still further.
Sir William Bragg (2 Jul 1862 - 12 Mar 1942)
He was a British scientist in solid-state physics who was a joint winner of the Noble Prize for physics for research on the determination of crystal structures in 1915. During WW I, he was appointed as an incharge of research on the detection and measurement of underwater sounds in connection with the location of submarines. He also constructed the wavelengths of X-rays. He was knighted in 1920.
Harriet Brooks (2 Jul 1876 - 17 Apr 1933)
She was a Canadian nuclear physicist who contributed a lot to the new science of radioactivity. She was probably the first to observe the recoil of the atomic nucleus during the emission of the nuclear particles at radioactive decay. Along with Rutherford, she demonstrated that the diffusion of the emanations of radium behaved like gas as well as had a high molecular weight. She died due to leukemia.
July 2 in Physics History - Deaths – Physicists died on July 2
Seth Barnes Nicholson (12 Nov 1891 - 2 Jul 1963)
He was an American astronomer who is known for discovering the 4 satellites of Jupiter. While photographing the 8th moon of Jupiter with the 36-inch Crossley reflector in 1914, he discovered the 9th satellite. He discovered two more satellites while working at Mt. Wilson Observatory. He also computed the orbits of several comets. His work was to observe the sun with the 150-foot solar tower telescope and to produce annual reports on sunspot activity. He measured the temperature of the moon, sunspots, and stars with Edison Pettit.