More than a hundred years ago, in 1905, Lise became only the second female to get a PhD in Physics in the world! She then became a university lecturer in Berlin, until she fled Nazi Germany and settled in Sweden. Here, along with chemists Fritz Strassmann and Otto Hahn, she discovered nuclear fission – where an element called uranium was hit very hard with subatomic particles called neutrons, causing it to split into lighter elements. This discovery led to the development of the first atomic bomb.