October 7 is the birth date of Danish physicist Niels Bohr  (1885-1862). Bohr has a special significance for Alpha Tau, for two reasons. The first reason is because he was one of the key contributors to the foundational discoveries in atomic physics at the beginning of the 20th century. Bohr played a critical role in elucidating and explaining the structure of the atom and the phenomenon of radiation release. The second reason is because of his bravery during World War II in
helping Jewish scientists and the entire Danish Jewish community escape from capture and death at the hands of the Nazis.
Niels Bohr grew up in Copenhagen into a prominent academic family, and earned a PhD in physics from the University of Copenhagen in 1911.  He moved to Cambridge University in England to work with two of the leading physicists of that period - J.J. Thomson, who discovered the existence of electrons, and Ernest Rutherford who discovered the existence of the atomic nucleus. Under the mentorship of Rutherford, Bohr studied the properties of atoms, and subsequently returned to the University of Copenhagen where he became a professor of theoretical physics. In 1920, he was appointed as director of the newly created Institute of Theoretical Physics. It was here that Bohr developed his own idea of what the structure of the atom looked like. 
According to the Bohr Model of the Atom, electrons revolve in stable orbits - each at a defined energy level - around the atomic nucleus. He theorized that electrons can jump from one energy level to another by absorbing or emitting electromagnetic radiation (see figure to the left) .
In 1922, Bohr was awarded the Nobel Prize in physics for “his services in the investigation of the structure of atoms and of the radiation emanating from them” .
We also have a special appreciation for Niels Bohr because of his courageous humanitarian activities leading up to and including World War II.
Thanks to Niels Bohr's engagement, scientists of Jewish background from Germany and Austria, and those who were opponents were able to flee from the Nazi regime. He is also thought to have aided in the rescue of the entire Jewish population of Denmark that was in danger of deportation to concentration camps after the German army occupied Denmark in 1943. 
Bohr was one of the great theoretical physicists of the early 20th century and had personal relationships with other leading physicists who lived in Europe. For example, he brought German physicist Werner Heisenberg, who received the Nobel Prize in physics in 1932 for the creation of quantum mechanics, to the University of Copenhagen from 1926-27. After the National Socialists (Nazis) came to power in Germany in 1933, many of Germany’s best scientific minds were forced to flee because of their Jewish descent or opposition to Nazism. Bohr arranged academic positions for many of them at his Institute in Copenhagen, or elsewhere in the world. Among the scientists he aided were Edward Teller, father of the hydrogen bomb, and Lise Meitner whose research into nuclear fission was key to the development of nuclear weapons during the war, and nuclear reactors to produce electricity after the war. [6,7]
In 1941, Heisenberg was the director of the German nuclear program and requested to have a meeting with Bohr in Copenhagen. The precise content of their discussion is not known, but it had something to do with Germany’s attempt to build an atomic bomb and its curiosity as to how far the American effort had proceeded. Bohr refused to cooperate with Heisenberg. In 1943, he received notice that he would be arrested by the German army as it occupied Denmark because he was partly Jewish on his mother’s side. He escaped by fleeing to Sweden. He is also given credit for convincing Swedish King Gustav V to grant asylum to the entire Danish Jewish community of 7800 persons, who thus escaped deportation to the concentration camps. [5,8]
As soon as he arrived in Denmark, Bohr was invited to come to the United States and participate as an advisor in the Manhattan Project, which was to produce the world’s first atomic bomb, and helped to end the war in the Pacific. Bohr’s contributions to the Manhattan Project may have been more moral and philosophical than scientific, it isn’t exactly known. 
At Alpha Tau, we are honored to remember and celebrate the contributions of Niels Bohr. First, we honor Bohr as a leading physicist in an area of central relevance to our company’s work. Second, we honor him as a great humanitarian who rescued a small Jewish community from the tragic fate of millions of European Jews. After the war, Bohr devoted himself both to advancing the frontiers of science and to promoting uses of atomic energy in ways that benefit humanity. 
Alpha Tau Medical is proud to be inspired by the legacy of Niels Bohr. We continue his work both in the realm of scientific research and in the arena of healthcare, by developing improved treatments for cancer, such as Alpha DaRT.