Environment

Earth’s Oscillating Core

While scientists have for decades believed that Earth’s inner core consistently rotates faster than the planet’s surface, there is new evidence that the core oscillates and actually changed direction in the six years from 1969 to 1974.

The discovery was made in part by examining seismic data from Soviet underground nuclear tests from 1971 to 1974. Without such blasts, only the less-revealing quake data are available. niversity of Southern California researchers say their findings explain the variations in the length of a day, which has wavered during recent decades.

from WordPress https://ift.tt/ScH3Q0d