1926-

American-born Danish physicist best known for his work on the structure of the atomic nucleus. Mottelson joined the Navy during World War II and was sent for officer's training at Purdue University, where he earned his undergraduate degree. Working with Aage Bohr and others in Europe after receiving his Ph.D., Mottelson viewed the nucleus as a liquid drop, which helped explain many of the properties exhibited during atomic interactions. This work was recognized with the 1975 Nobel Prize for Physics, which he shared with Bohr and James Rainwater.