Niels Henrik David Bohr (born: October 7, 1885 / died: November 18, 1962 )
Niels Henrik David Bohr was born in Copenhagen.   His father was an eminent physiologist and was largely responsible for awakening his interest in physics while still at school, his mother came from a family distinguished in the field of education. After matriculation at the Gammelholm Grammar School in 1903, he entered Copenhagen University where he came under the guidance of Professor C. Christiansen, a profoundly original and highly endowed physicist, and took his Master's degree in Physics in 1909 and his Doctor's degree in 1911. 

While still a student, the announcement by the Academy of Sciences in Copenhagen of a prize to be awarded for the solution of a certain scientific problem, caused him to take up an experimental and theoretical investigation of the surface tension by means of oscillating fluid jets. This work, which he carried out in his father's laboratory and for which he received the gold medal, was published in the Transactions of the Royal Society, 1908.

Bohr's subsequent studies, however, became more and more theoretical in character, his doctor's dissertation was a purely theoretical piece of work on the explanation of the properties of the metals with the aid of the electron theory, which remains to this day a classic on the subject.  It was in this work that Bohr was first confronted with the implications of Planck's quantum theory of radiation.

In the autumn of 1911 he worked at Cambridge, where he followed the experimental work going on in the Cavendish Laboratory under Sir J.J. Thomson.  At the same time he pursued own theoretical studies.  In the spring of 1912 he was at work in Professor Rutherford's laboratory in Manchester.  Rutherford was conducting his fundamental inquiries into the radioactive phenomena.  Bohr carried out a theoretical piece of work on the absorption of alpha rays which was published in the Philosophical Magazine in 1913.   He then continued on to a study of the structure of atoms based on Rutherford's discovery of the atomic nucleus.  By introducing concepts borrowed from the Quantum Theory, as established by Planck, he succeeded in working out and presenting a picture of atomic structure that still serves as a model of the physical and chemical properties of the atom.

Niels Bohr died in Copenhagen on November 18, 1962.