The precise radius of the inner core was not measured until relatively recently.How was this accomplished?

Question

Quizplus · Accepted Answer

The precise radius of the inner core was determined by using a precisely known, underground nuclear weapons test in the Nevada desert in the early 1960s. When the bomb went off, seismometers around the world recorded the shock waves it produced as they traveled through the Earth, and scientists were able to use this data to determine the speed and path of the waves, and thus the size and location of the inner core.

The Precise Radius of the Inner Core Was Not Measured