April 19 in Physics History
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birthdays & deaths
Explore all birthdays & deaths of physicists occurred on this day with their short biography!
physics Events
Know all important discoveries made by physicists & events happened on this day with complete information!
April 19 in Physics History - Births – Physicists born on April 19
Gustav Theodor Fechner (19 Apr 1801 - 18 Nov 1887)
He was a German physicist and philosopher who formulated Fechner’s law that states that the intensity of a sensation increases as the logarithm of the stimulus. He was the key figure in the foundation of psychophysics. Psychophysics is a science that deals with quantitative relations between sensations and the stimuli producing them. He also proposed a mathematical expression of the theory about the difference between two stimuli. He was an animist in philosophy.
Albert Wallace Hull (19 Apr 1880 - 22 Jan 1966)
He was an American physicist who invented the magnetron and the thyratron. He independently discovered the Powder method of X-ray analysis of crystals. This method allows the study of crystalline material in a finely microcrystalline state. He also studied noise measurements in diode and triode and he took interest in metallurgy and glass science. He wrote a paper on the effect of a uniform magnetic field on the motion of electrons between coaxial cylinders.
April 19 in Physics History - Deaths – Physicists died on April 19
Warren De la Rue (15 Jan 1815 - 19 Apr 1889)
He was a British chemist, astronaut, and inventor who was elected as the fellow of the Royal Society of London and was awarded its Royal medal in 1864. He is known for his excellent work in astronomical photography. His method made nearly all modern astronomical observations. He was also a member of the royal astronomical society and also received the gold medal in 1862.
Zygmunt Florenty von Wroblewski (28 Oct 1845 - 19 Apr 1888)
He was a Polish physicist who improved the method of Cailletet and was successful in liquefying permanent gases such as nitrogen and carbon monoxide in large quantities. Hydrogen was first liquefied by him and he achieved the static liquefaction of Oxygen and air in 1883. He might have given us a hint of strange electrical properties at very low temperatures but his research was not completed because of his accidental death. He died as a result of fire when he overturned a kerosene lamp in his laboratory.
Walter Kohn (9 Mar 1923 - 19 Apr 2016)
He was an Austrian-American physicist who shared the Noble Prize in chemistry in 1998. His share of the prize was for the development of his density-function theory. This theory revolutionized material science in such a way that it has been said it has been referenced in about half of all publications in quantum chemistry that have followed. He also made contributions to the physics of semiconductors, superconductivity, catalysis and surface physics.
April 19 in Physics History - Events – Physics Events of April 19
The First Indian Satellite - Aryabhta
The first satellite of India, Aryabhata was launched from Volgograd launch station, Russia in 1975. Its mass was 360 kg and it was built during 20 months by the Indian Space Research Organization (ISRO). It was covered in solar cells except for the top and the bottom. It was designed to carry out experiments in aerodynamics and solar physics however after only 4 days in orbit, the experiments were ended because of a power failure. It orbited the Earth for nearly 17 years and then it entered the earth’s atmosphere in 1992.
The First Black & Women Astronaut
The US announced that the first Black astronaut would be Guion S. Bluford, and the first woman astronaut would be Sally K. Ride in 1982. Bluford became the first black American astronaut on 30th August 1983. Ride becomes the first American woman to orbit the earth when she flew abroad with Challenger on 18 June 1983.
The First Space Station
Salyut 1 was launched on a proton rocket by the Soviet Union in 1971. It was the first-ever Space station in the orbit of Earth having only a single main module. Its first crew members were launched in Soyuz 10 but due to a failure in the docking mechanism, they were not able to board the Space station. The second crew that arrived in Soyuz 11 remained on board for 23 days but they all killed because a pressure equalization valve reentry capsule opened prematurely. The Salyut 11 entered into the earth’s atmosphere on 11th October 1971.
