In the case of our 'string around the Earth' puzzle, the radius is being increased by 15cm, so we need to know that as a fraction of the original radius. So what is the radius to start with?

"The details of this big event are still a bit of a mystery, but we've added another piece of the puzzle when it comes to our knowledge of the Earth's inner core." These findings may explain why ...

A new study challenges theories regarding the origins of a significant transition through the Earth's ice ages. The research provides fresh insights into the ocean's role in climate during the ...