Inge Lehmann

Inge Lehmann ForMemRS (May 13, 1888 – February 21, 1993), was a Danish seismologist who discovered the Earth's inner core. In 1936 she postulated from existing seismic data that the Earth's core is not a single molten sphere, but that an inner core exists, which has physical properties that are different from those in the outer core. This conclusion was quickly accepted by seismologists, who up to this time had not been able to propose a workable hypothesis for the observation that the P-wave created by earthquakes slowed down when it reached certain areas of the inner Earth.

Inge Lehmann was born and grew up in Østerbro, a part of Copenhagen. She was the daughter of the experimental psychologist Alfred Georg Ludvik Lehmann (1858–1921). She received her school education at a pedagogically progressive high school led by Hanna Adler, an aunt of Niels Bohr. According to Lehmann, her father and Adler were the two most significant influences for her intellectual development. After having finished school, she studied, with some interruptions due to poor health, mathematics at the University of Copenhagen and University of Cambridge. She continued her studies of mathematics in Cambridge from 1910-1911 at Newhan College. In 1911 Lehmann returned from Cambridge feeling exhausted from the work, so she decided to put studies aside for a while. Lehmann developed good computational skills from an actuary office she worked for a few years until she continued her studies at Copenhagen University in 1918. She completed the candidates magisterii degree in physical science and mathematics in two years. When she returned to Denmark in 1923 she accepted a position at Copenhagen University as an assistant to J.F. Steffensen, the professor of actuarial science.

http://en.wikipedia.org/wiki/Inge_Lehmann

http://www.kvinfo.dk/side/171/bio/1800/

http://sciencenordic.com/female-scientist-who-discovered-core-earth