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Inge Lehmann

1888-1993. Danish seismologist and geophysicist

 Inge Lehmann

Photo: Wikicommons

Inge Lehmann (May 13, 1888 – February 21, 1993) was a seismologist and geophysicist. In 1936, she wrote an article on P-waves where she argued that the Earth has a solid inner core inside a molten outer core. Before that, seismologists believed Earth's core to be a single molten sphere, being unable, however, to explain careful measurements of seismic waves from earthquakes, which were inconsistent with the Earth having a single molten core. Lehmann analysed the seismic wave measurements and concluded, that Earth must have a solid inner core and a molten outer core to produce seismic waves that matched the measurements. Other seismologists tested and then accepted Lehmann's explanation, which is now known as the Lehmann Discontinuity.

Quite unlike her contemporaries, Lehmann was educated at a mixed gender school, as women back then in 1880’s were usually bestowed with such rights. Soon she realized the apathy and was much frustrated with the treatment of women in science. As she at one point said to her nephew: "You should know how many incompetent men I had to compete with - in vain."

Lehmann received many honours for her outstanding scientific achievements, among them the Gold Medal of the Danish Royal Society of Science and Letters (1965); the election as a Fellow of the Royal Society in 1969; the William Bowie Medal (1971, as the first woman) at which point, she was described as ‘the master of a black art for which no amount of computerizing is likely to be a complete substitute’; and the Medal of the Seismological Society of America in 1977. She was awarded honorary doctorates from Columbia University in 1964 and from the University of Copenhagen in 1968, as well as numerous honorific memberships.

The asteroid 5632 Ingelehmann was named in her honour.

In 1997, the American Geophysical Union established the Inge Lehmann Medal to honour "outstanding contributions to the understanding of the structure, composition, and dynamics of the Earth’s mantle and core."

On the 127th anniversary of her birth, Google dedicated its worldwide Google Doodle to her

GEUS (Geological Survey of Denmark and Greenland), UCLA (University of California) and The Local

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