Inge Lehmann (1888-1993) performed research that upended the way scientists thought of the center of the planet.
Inge Lehmann (1888-1993) performed research that upended the way scientists thought of the center of the planet.
Special thanks to Mercedes-Benz, our exclusive sponsor this month! From their early days, Mercedes-Benz has built a legacy championing women to achieve the unexpected. Join us all month long as we celebrate women who have led dynamic lives that have shifted, evolved and bloomed, often later in life, eventually achieving the success for which they were destined from the start.
History classes can get a bad rap, and sometimes for good reason. When we were students, we couldn’t help wondering... where were all the ladies at? Why were so many incredible stories missing from the typical curriculum? Enter, Womanica. On this Wonder Media Network podcast we explore the lives of inspiring women in history you may not know about, but definitely should.
Every weekday, listeners explore the trials, tragedies, and triumphs of groundbreaking women throughout history who have dramatically shaped the world around us. In each 5 minute episode, we’ll dive into the story behind one woman listeners may or may not know–but definitely should. These diverse women from across space and time are grouped into easily accessible and engaging monthly themes like Educators, Villains, Indigenous Storytellers, Activists, and many more. Womanica is hosted by WMN co-founder and award-winning journalist Jenny Kaplan. The bite-sized episodes pack painstakingly researched content into fun, entertaining, and addictive daily adventures.
Womanica was created by Liz Kaplan and Jenny Kaplan, executive produced by Jenny Kaplan, and produced by Liz Smith, Grace Lynch, Maddy Foley, Brittany Martinez, Edie Allard, Lindsey Kratochwill, Adesuwa Agbonile, Carmen Borca-Carrillo, Taylor Williamson, Ale Tejeda, Sara Schleede, and Alex Jhamb Burns. Special thanks to Shira Atkins.
Original theme music composed by Miles Moran.
We are offering free ad space on Wonder Media Network shows to organizations working towards social justice. For more information, please email Jenny at pod@wondermedianetwork.com.
Follow Wonder Media Network:
Hello! From Wonder Media Network, I’m Jenny Kaplan. This is Womanica.
This month, we're highlighting women who've led dynamic lives. Ones that have shifted, evolved and bloomed, often later in life.
Today, we’re talking about a woman who discovered the composition of the Earth’s inner core. She worked for years as an assistant, in administrative roles. But she never stopped pursuing her own research, which would eventually upend the way scientists thought of the center of the planet. And she figured it all out thanks to some ingenuity and earthquakes.
Please welcome Inge Lehmann.
Inge was born on May 13, 1888 near Copenhagen, Denmark. Her family raised her untraditionally, in a progressive household.
As a young girl, Inge attended a co-educational private school, which was unusual for the time. The school treated boys and girls on an equal plane, intellectually. This instilled in her an early notion of gender equality.
She later reflected that this experience “brought some disappointment [to me] later in life when I had to recognize that this was not the general attitude.”
Inge went on to pursue higher education at the University of Copenhagen. There, she studied mathematics while also taking classes in astronomy, chemistry, and physics. She spent several years there before continuing her education at Newnham College, one of the women’s colleges at the University of Cambridge.
She enjoyed her time in England but the differences in the way girls and women were treated came as a surprise to her. Women were allowed to take courses and attend lectures. But, they were not actually granted university degrees until several decades later.
Still, Inge overworked herself to the point of extreme exhaustion and had to return home to Denmark after just about a year. Back in Copenhagen, she spent several years working in an actuary’s office. Eventually, she resumed her degree in mathematics at the University of Copenhagen, and graduated in 1920.
It was largely chance that led her to seismology. In 1925, she became s an assistant to the mathematician Niels Erik Nörlund. Niels had just become the director of the Royal Danish Geodetic Institute. And he tasked Inge with setting up seismological observatories in both Denmark and Greenland.
Inge also started learning how seismology could be used to learn about the Earth’s inner composition. Essentially, earthquakes cause two main types of seismic waves: P waves, and then S Waves. Scientists could use these waves to figure out what the insides of the planet were made of – based on the way the waves moved through liquids and solids. Inge studied more about the topic on her own time.
Inge’s seismological career was moving swiftly. The following year she earned a master’s degree in geodesy, a branch of mathematics dealing with the shape and area of the earth.
With her new degree, she became the chief of the seismological department at the Geodetic Institute.
Her role was largely administrative but she made time for research.
This was long before computers existed, but she still needed to analyze large sets of data. So, she would use cardboard oatmeal boxes. She would write down all the data points on pieces of cardboard and puzzle over them.
One particularly important moment came in 1929, when an earthquake hit near New Zealand. Something strange happened with the P-waves – they showed up across the world in Europe, at seismic stations. If the center of the earth was liquid – as scientists thought – the waves should have been deflected by the planet’s core.
In 1936 when Inge was in her late 40s, she published a paper simply titled “P.” In it, she suggested the existence of a different internal structure of the earth. Instead of it being all liquid, there were two parts. An inner core, which was solid. Surrounded by a liquid outer core. What separated the two is now known as the Lehmann Discontinuity.
Inge’s findings were indeed correct. And in the following years, other scientists corroborated her hypothesis.
In step with other female scientists of her time, Inge never married. Marriage likely would have meant the end of her career as she knew it. She retired in 1953, but continued her research.
She received dozens of honors which recognized both her scientific achievement as well as her achievement as a woman in a male-dominated field. As she once said, "you should know how many incompetent men I had to compete with — in vain".
In 1971, she was awarded the American Geophysical Union’s highest honor, the William Bowie Medal.
Inge died in 1993, at the age of 104.
In 2015, Inge’s name was immortalized in two unique ways: An asteroid and a new beetle species.
All month, we’re highlighting dynamos. For more information, find us on Facebook and Instagram @womanicapodcast.
Special thanks to Liz Kaplan, my favorite sister and co-creator.
Talk to you tomorrow!