INGE LEHMANN ForMemRS (13 May 1888 – 21 February 1993) was a
Danish seismologist and geophysicist . In 1936, she discovered that
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 this
idea. Lehmann analysed the seismic wave measurements and concluded
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. Lehmann
was also the longest-lived woman scientist, having lived for over 104
* 1 Early life and education
* 2 Career
* 3 Awards and honors
* 4 Key publications
* 5 Bibliography
* 6 See also
* 7 References
* 8 External links
EARLY LIFE AND EDUCATION
Inge Lehmann was born and grew up in
Østerbro , a part of Copenhagen
. Her mother was Ida Sophie Tørsleff; her father was experimental
psychologist Alfred Georg Ludvik Lehmann (1858–1921). She received
her school education at a pedagogically progressive high school led by
Niels Bohr 's aunt. According to Lehmann, her father
and Adler were the most significant influences on her intellectual
She studied mathematics at the University of
University of Cambridge
University of Cambridge , interrupted by poor health. She continued
her studies of mathematics in Cambridge from 1910 to 1911 at Newnham
College . In 1911, she returned from Cambridge feeling exhausted from
the work and put her studies aside for a while. She developed good
computational skills in an actuary office she worked in for a few
years until she resumed studies at
Copenhagen University in 1918. She
completed the candidatus 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.
She was a very shy girl, and did not enjoy being in the spotlight too
much. Even when she grew older, she was still very shy. She was
schooled in a private school, after taking the entrance exam for
Copenhagen University with the first rank mark. She started freshman
courses in mathematics, chemistry and physics. It took her an
exceptionally long time to get a degree: in 1911 she had returned to
Copenhagen after a year at Cambridge University completely burned out;
she then abandoned her studies to do actuarial work for an insurance
company. She did actuarial work until 1918, when she returned to
university, finally graduating with a mathematics degree in 1920, aged
32. She then started working as an assistant in Copenhagen
University's actuarial department and later shifted her interest to
seismology work with Professor Niels Norlund. She learned that the
internal structure of our planet can be understood through the study
of earthquake data. She travelled a lot of places just to get a better
understanding of the earth's movement.
Lehmann had a younger sister, Harriet, who became a movie writer and
who had family and children in contrast to Lehmann, who lived by
herself all her life.
A modern understanding of the
Lehmann discontinuity : velocity
of seismic S-waves in the
Earth near the surface in three tectonic
provinces: TNA = Tectonic North America SNA = Shield North America and
ATL = North Atlantic.
In 1925 Lehmann became an assistant to the geodesist Niels Erik
Nørlund , who assigned her the task of setting up seismological
observatories in Denmark and
Greenland . Based on her studies in
seismology, in 1928 she earned the magister scientiarum degree
(equivalent to an MA) in geodesy and accepted a position as state
geodesist and head of the department of seismology at the Geodetical
Institute of Denmark led by Nørlund. Lehmann looked into improving
the coordination and analysis of measurements from Europe's
seismographic observatories, as well as many other scientific
In a paper titled P' (1936), Lehmann was the first to interpret P
wave arrivals—which inexplicably appeared in the P wave shadow of
the Earth's core—as reflections from an inner core, for example from
1929 Murchison earthquake
1929 Murchison earthquake . Other leading seismologists of
the time, such as
Beno Gutenberg ,
Charles Richter , and Harold
Jeffreys , adopted this interpretation within two or three years, but
it took until 1971 when the interpretation was shown correct by
computer calculations. Lehmann was significantly hampered in her work
and maintaining international contacts during
World War II
World War II and the
German occupation of Denmark. She served as the Chair of the Danish
Geophysical Society in 1940 and 1944 respectively.
In 1952, Lehmann was considered for a professorship in geophysics at
Copenhagen University, but was not appointed. In 1953, she retired
from her position at the Geodetic Institute. She moved to the US for
several years and collaborated with
Maurice Ewing and
Frank Press on
investigations of Earth\'s crust and upper mantle . During this work,
she discovered another seismic discontinuity, which lies at depths
between 190 and 250 km and was named for her, the Lehmann
discontinuity . Francis Birch noted that the "Lehmann discontinuity
was discovered through exacting scrutiny of seismic records by a
master of a black art for which no amount of computerization is likely
to be a complete substitute."
AWARDS AND HONORS
Lehmann received many honors for her outstanding scientific
achievements, among them the Gordon Wood Award (1960), the Emil
Wiechert Medal (1964), the Gold Medal of the Danish
Royal Society of
Science and Letters (1965), the
Tagea Brandt Rejselegat (1938 and
1967), her election as a Fellow of the
Royal Society in 1969, the
William Bowie Medal (1971, as the first woman), and the Medal of the
Seismological Society of America in 1977. She was awarded honorary
Columbia University in 1964 and from the University of
Copenhagen in 1968, as well as numerous honorific memberships.
5632 Ingelehmann was named in her honor and in 2015
(which was the 100th anniversary of women's suffrage in Denmark)
Lehmann got, in recognition of her great struggle against the
male-dominated research community that existed in Denmark in the
mid-20th century, a new beetle species named after her: Globicornis
(Hadrotoma) ingelehmannae sp. n., Jiří Háva & Anders Leth Damgaard,
Because of her contribution to geological science, in 1997, the
American Geophysical Union
American Geophysical Union established the annual
Inge Lehmann Medal
to honor "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.
A new memorial dedicated to Lehmann was installed on
Frue Plads in
Copenhagen in 2017. The monument is designed by
Elisabeth Toubro .
* Lehmann, Inge (1936). "P'". Publications du Bureau Central
Séismologique International. A14 (3): 87–115.
* Lehmann, Inge (1987). "
Seismology in the Days of Old". EOS . 68
* Swirles, Lady Jeffreys, Bertha (1994). "Inge Lehmann:
Reminiscences". Quarterly Journal of the Royal Astronomical Society.
35 (2): 231.
* Kousholt, Bjarne. "
Inge Lehmann og Jordens kerne" ISBN 8750209574
Richard Dixon Oldham
List of geophysicists
List of geophysicists
* ^ A B "Lehmann, Inge". Complete Dictionary of Scientific
Biography . Detroit, MI: Charles Scribner's Sons. 2008. Retrieved 15
* ^ "
Inge Lehmann - Biography, Facts and Pictures". Famous
Scientists. The Art of Genius. Retrieved 2017-07-02.
* ^ "Lehmann; Inge (1888–1993)". The Royal Society: Past Fellows.
Retrieved 24 September 2013.
* ^ Bolt, Bruce A. (January 1994). "Inge Lehmann". Physics Today.
47 (1): 61.
Bibcode :1994PhT....47a..61B. doi :10.1063/1.2808386 .
* ^ "WiP: Herstory: Spotlight Scientist: Inge Lehmann". Purdue
University. Retrieved 15 October 2013.
* ^ Knopoff, Leon. "Lehmann, Inge". UCLA. Retrieved 15 October
* ^ Bolt, Bruce. "Inge Lehmann". UCLA. Retrieved 15 October 2013.
* ^ "www.encyclopedia.com : Inge Lehmann". Encyclopedia.com.
* ^ A B C "Inge Lehmann". Famous Scientists.
* ^ Gillispie, Charles. Complete dictionary of scientific
biography. Detroit, Mich.: Charles Scribner's Sons. p. 234.
* ^ "Lehmann had a younger sister, Harriet, who became an actress
and who had family and children in contrast to Lehmann, who lived by
herself all her life; from google (
Inge Lehmann married) result 2".
* ^ "She sacrificed marriage and family for her career, since women
at that time could almost never have both; from google (Inge Lehmann
married) result 1".
* ^ "She had not married and had no children; from google (Inge
Lehmann married) result 3".
* ^ Figure patterned after Don L Anderson (2007). New Theory of the
Earth (2nd ed.). Cambridge University Press. p. 102, Figure 8.6. ISBN
0-521-84959-4 . ; Original figure attributed to Grand and Helmberger
* ^ Maiken, Lolck (2008). ""Lehmann, Inge." Complete Dictionary of
Scientific Biography". Gale Virtual Reference Library. Vol. 22: Gale.
pp. 232–236. Retrieved 22 May 2015.
* ^ "Inge Lehmann: Discoverer of the Earth\'s Inner Core". American
Museum of Natural History.
* ^ Lehmann, I. (1936): P’, Publications du Bureau Central
Seismologique International, Série A, Travaux Scientifique, 14,
* ^ Bolt, Bruce A. (1987). "50 years of studies on the inner core".
EOS . 68 (6): 73,80–81.
* ^ A B Dahlmann, Jan (23 January 2005). "
Inge Lehmann og Jordens
Ingeniøren (in Danish). Retrieved 14 May 2015.
* ^ "Fellowship of the Royal Society". Royal Society. Retrieved May
* ^ "A New Species Of
Globicornis (Hadrotoma) (Coleoptera,
Dermestidae, Megatominae) From Baltic Amber". amber-inclusions.dk.
* ^ "
Inge Lehmann Medal". American Geophysical Union.
* ^ "Inge Lehmann". Encyclopedia.com.
* ^ Gander, Kashmira (12 May 2015). "Inge Lehmann\'s 127th
Birthday: Pioneering seismologist celebrated by
Google Doodle". The
Independent . Retrieved 12 May 2015.
* ^ Kevin McSpadden (13 May 2015). "New
Google Doodle Honors
Pioneering Seismologist Inge Lehmann". Time.com. Retrieved 13 May
* ^ "Inge Lehmann’s 127th Birthday". google.com.
* ^ "Skulptur på
Frue Plads i København er et minidrys
feministisk retfærdighed" (in Danish). Politiken. Retrieved 8 July
Inge Lehmann at