NASA says giant China dam shifted Earth’s axis and made days shorter

The Three Gorges Dam in China has had a surprising impact on Earth’s rotation, causing our days to lengthen ever so slightly, according to a new study from NASA

Despite the widely accepted belief that it’s virtually impossible to alter the passage of time on Earth, NASA has revealed that a man-made structure in China has done just that.

China’s Three Gorges Dam, constructed nearly 18 years ago, has effectively shifted Earth’s axis by almost an inch, resulting in a slight elongation of our days. Work on this colossal dam commenced in 1994 and it wasn’t until 2006, over a decade later, that the project was completed.

The dam transformed the Yangtze River into a reservoir holding 10 trillion gallons of water, generating an average of 0.54 TWh of electricity daily, sufficient to power 5.4 million homes for a month.

While the dam is an engineering wonder, it has also had unexpected effects on Earth’s rotation, something most scientists previously considered unachievable.

The dam’s 10 trillion gallons of water add weight to the Earth’s crust above sea level, redistributing mass within the planet and impacting its moment of inertia. Scientists at NASA’s Goddard Space Flight Centre have confirmed that this additional weight has caused Earth’s rotation axis to shift by approximately two centimetres, or about three-quarters of an inch, reports the Express US.

Although three-quarters of an inch may seem insignificant compared to Earth’s vast size, from a planetary physics perspective, it’s substantial. As more mass moves away from its axis, Earth’s rotation slightly decelerates.

This impact mirrors natural occurrences like the 2004 Indian Ocean tsunami, which altered the Earth’s axis and shortened the day by a few microseconds due to tectonic shifts. The Three Gorges Dam demonstrates just how significantly human activity can influence Earth’s rotation in comparison to natural disasters.

The dam, a wonder of contemporary engineering, competes with the electrical outputs of some nations and lessens China’s reliance on fossil fuels for electricity production. It also plays a crucial role in flood management in the area.

However, it came at a terrible price, as the construction of the dam displaced 1.2 million people. The flooded region extends about 370 miles, submerging ecosystems that evolved over centuries and dramatically changing the landscape.

Research, including a study published in Geophysical Research Letters in 2010, suggests that mega-projects like the Three Gorges Dam can have a profound effect on the subtle shifts in Earth’s balance.

Many experts advocate for thorough consideration of environmental and geophysical impacts before undertaking similar projects.

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