Inge Lehmann (13 May, 1888 – 21 Feb, 1993), a Danish seismologist and geophysicist who discovered the Earth’s inner core, was born exactly 127 years ago today. Google celebrates her birthday today with a brand new Doodle. In 1936,, Ms. Lehmann suggested that Earth’s inner core had physical properties that were distinct from that of the outer core. This was in addition to the fact that there wasn’t one molten sphere at the core. Others, including prominent seismologists, were unable to offer a plausible hypothesis as to why the P-wave caused by earthquakes slows down in certain parts of the Earth. However, they quickly accepted the conclusion. Inge Lehmann (1888-1993). (Image: annalsofgeophysics.eu) Early life and education Ms. Lerhmann was born and brought up in Osterbro, one of the 10 official districts of Copenhagen. Alfred Georg Ludvik Lehmann was her father and an experimental psychologist. She attended a progressive, pedagogically-oriented high school as a child. Hanna Adler was her aunt. According to her, her father and aunt were her most important influences in her intellectual growth. At the University of Cambridge and University of Copenhagen, she studied mathematics. According to a UCLA, Berkeley, paper “However, serious overwork from accelerated study to pass the entrance examinations led to her return home in December 1911. Slowly, her recovery was not quick and she couldn’t consider returning to university. In 1918, she continued studying at Copenhagen University. She completed her candidates magisterii degree at Cambridge in math and physical science within two years. Inge Lehmann 1932. (Image: Wikimedia) Career In 1923, she accepted a position as an assistant to J.F. Steffensen is the Copenhagen University professor of actuarial sciences. In 1928,, she worked as an assistant to Niels Erik Norlund (a geodesist is a scientist that measures the Earth and determines its exact coordinates). She was then given the responsibility of setting up observatories in Greenland or Denmark. This was when her fascination with seismology began to blossom. After passing her exam in 1928 geodesy, she became a state geodesist. She also headed the seismology department at the Geodetical Institute of Denmark. Norlund was the head of this department. Google dedicated its worldwide Google Doodle to Inge Lehmann on 13 May, 2015, to celebrate the 127th anniversary of her birth. Image: Google. Inge Lehmann’s most significant scientific discovery was when she studied data about a large earthquake that struck New Zealand in 1929.. She noticed that several seismic waves bounced off the Earth’s core boundary while comparing various sets of data. This seismic noise referred to as the’shadow area’ in her opinion. It was due to an inner core of different materials. Her findings were quickly adopted by the scientific community. Scientists previously believed that Earth’s interior consisted only of one molten sphere. This was in contrast to the outer and inner cores. She was awarded and honored with many honours during her lifetime: 1960 The Gordon Wood Award. 1964 The Emil Wiechert Medal. Columbia University honorary doctorate. 1965 The Gold Medal of Danish Royal Society of Science and Letters. 1967, 1938. – The Tagea Brandt Rejselegat. 1968 is an honorary doctorate awarded by the University of Copenhagen. 1969 Fellow of The Royal Society. 1971 The William Bowie Medal, which was awarded to the first woman. 1977 The Medal of the Seismological Society of America. 1997 The American Geophysical Union created the Inge Lehmann medal, to honor “outstanding contributions towards the understanding of structure, composition and dynamics of Earth’s core and mantle.” Google+ Video: Inge Lehmann Google Doodle
