Earth’s Core Oscillates – Just Not in the Way Previously Thought

University of Southern California scientists recently found evidence that our planet’s core oscillates and not necesarily in the way we thought. Using data from the 1970s in the United States and Russia, researchers have made modern discoveries in the new millennium. This new information changes what we previously believed to be true about Earth’s movement.

A New Paper is Released:

The academic paper “investigate[s] the differential rotation of Earth’s inner core relative to the mantle using pairs of precisely located nuclear explosions…”

According to Science Daily and based on a paper published in Science Advances, The study “shows that the inner core changed direction in the six-year period from 1969-74.” In addition “The scientists say their model of inner core movement also explains the variation in the length of day…”

Where the Data Came From:

Utilizing the Large Aperture Seismic Aray at a US military base in Montana, researchers” found the inner core rotated slower than previously predicted, approximately 0.1 degrees per year.” The study also used data from Soviet era underground nuclear explosions in the 1970s.

Results from the Oscillation work:

According to their paper: “”We went into this expecting to see the same rotation direction and rate in the earlier pair of atomic tests, but instead we saw the opposite. We were quite surprised to find that it was moving in the other direction.” There was more noteworthy information to share.

The paper also stated: “our latest observations show that the inner core spun slightly slower from 1969-71 and then moved the other direction from 1971-74.” and “We also note that the length of day grew and shrank as would be predicted.”

What is Oscillation?

According to Vocabulary: “Oscillation is the process of moving back and forth regularly.” Their physics definition of oscillation is: “a regular periodic variation in value about a mean.”

What is Earth’s Core?

Education of National Geographic explains that the Core “is the very hot, very dense center of our planet. The ball-shaped core lies beneath the cool, brittle crust and the mostly-solid mantle.” It further explains that “the core is found about 2,900 kilometers (1,802 miles) below Earth’s surface…” The core sits inside the planet and is the inner most part of it.

Sometimes, as in the above graphic, the core is split into the inner and outer core. The core is generally believed to cotain a mix of iron and nickel.

The core is surrounded by the mantle and then the crust. The crust is the last layer of the physical planet. The core itself is broken up into the inner and outer core.

The Future of Earth’s Oscillation and Earthquake Research:

What is the future value of this for earthquake research moving forward is unclear. What we do know is that some of the geological information believed to be accurate, might not be. And in the search for earthquake data – turning over every rock could be useful. Certainly future scientists will have new information to base their earthquake forecasting on due to this report.

Thank you for reading our blog post about Earth’s oscillation.

Sources of Information:

Science Daily Article: The Earth moves far under our feet: A new study shows the inner core oscillates.

Science Advances: Seismological observation of Earth’s oscillating inner core, June 2022