Niels Bohr was a Danish physicist that worked on the Manhattan project and had the undercover identity of Nicholas Baker for security reasons. He came up with the theories that electrons travel in orbits around the atom's nucleus. Another theory was that the chemical properties of the elements was largely determined by the number of electrons in the outer orbits. Lastly that an electron could drop from a higher-energy orbit to a lower one, emitting a photon of discrete energy. Bohr fled Copenhagens escape to Natzi prosecution under HItler. He also traveled to New Mexico to take part as a consultant for the Manhattan Project and be their when they dropped the practice bomb.