April 29, 1894 – Birth of Marietta Blau, she identified traces of atomic particles that allowed protons to be distinguished from alpha particles

Marietta Blau en el laboratorio

She studied Physics and Mathematics at the University of Vienna, presenting her doctoral thesis in 1919. She wanted to be a professor, but the fact that she was a woman and a Jew prevented her from doing so.


  • 1921 - The theoretical and practical foundations of radiology.
  • 1923 - The interaction of ionizing radiation in a photographic emulsion could be used for the detection of particles emitted in nuclear reactions. The goal was to distinguish protons from alpha particles.
  • 1932 - At the Radium Institute in Paris, he worked with Marie Curie and Fréderic Joliot and, back in Vienna, he investigated, together with Hertha Wambacher, a method for detecting and determining the energy of alpha particles, based on the adaptation from photographic emulsions to the needs of nuclear physics, receiving, in 1937, the Ignaz L. Lieben Prize.
  • 1937 - They requested to be able to exhibit their photographic plates at the observatory of the University of Innsbruck on Hafelekar, a mountain 2,300 meters high. After several months they discovered that the nuclear reactions induced by the cosmic rays in the nuclei of the emulsions created a new pattern of traces whose trajectories started from a common center, which, due to their shape, they called "disintegration stars".
  • She moved to Mexico, where Albert Einstein had found her a job at ESIME (Superior School of Mechanical and Electrical Engineering) of the National Polytechnic Institute (IPN), being her only woman. She there she studied the effect of solar radiation and radioactivity on minerals and springs in various areas of the country.
  • 1944-she emigrates to the United States to work in a company developing several devices for the use of isotopes and patenting some of them. Subsequently, Columbia University contracted her as a scientist to develop a research program, based on her photographic detection method, to analyze the particles produced by fission reactors. Two years later, she got a position at Brookhaven National Laboratory, where she was able to put this program into practice.

But the decade that was away from the scientific world took its toll. In 1950, Cecil Powell received the Nobel Prize for the photographic method of particle identification and for the discovery of the pion. He himself recognized that he began to use this method after knowing the publications of Blau and Wambacher.

In 1956, she worked as an associate professor at a small private university in Miami, where she successfully established a particle physics laboratory and was able to continue her research.

If you want to know more about this scientist, click on the following link: Marietta Blau

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