Happy birthday to Danish #seismologist Inge Lehmann (1888 – 1993) who demonstrated that the Earth's core is not a single molten sphere, but contained an inner solid core, in ‘36. She was a pioneer #womanInScience, a brilliant seismologist & lived to be 105.
As she first postulated, the #earth has roughly 3 equal concentric sections: mantle, liquid outer core & solid inner core. 🧵1/n
