NASA confirm that huge man-made dam is slowing the Earth's rotation and making days longer

If you've ever wondered whether it's possible to lengthen a day, then a project in China might just have the answer for you.

According to NASA, China’s colossal Three Gorges Dam has actually slowed the rotation of the Earth.

Yes, seriously.

The same hydroelectric dam that displaced over a million people and flooded entire cities is now responsible for adding a fraction of time to each day on Earth.

NASA geophysicist Dr. Benjamin Fong Chao revealed that the mega-dam, located on the Yangtze River in Hubei province, has increased the length of a day by 0.06 microseconds, he said on Reddit.

That’s about 60 nanoseconds per day. Not exactly enough to get much done, but still alarming.

“For reference, this amounts to a bit more than 3 days over the entire age of the universe,” Dr. Chao explained.

The dam holds around 40 cubic kilometres of water — that’s 10 trillion gallons — stored 175 meters above sea level.

This monumental shift in Earth’s mass distribution has altered our planet’s moment of inertia. Basically, it’s the same principle as a spinning figure skater extending their arms to slow down.

“Any time you shift mass around, you change the Earth’s rotation. The effect is very small, but measurable,” Dr. Chao said.

NASA confirmed that the Three Gorges Dam has also shifted Earth’s axis by roughly two centimeters.

Let that sink in — one engineering project has done what only massive earthquakes used to do.

For comparison, the 2004 Indian Ocean earthquake (magnitude 9.1) shortened the day by 2.68 microseconds. The Three Gorges Dam, by contrast, lengthened it — ever so slightly.

Even though it sounds like something from science fiction, the numbers are real. And it has Reddit users and science nerds alike buzzing about just how much humanity is capable of changing the planet, sometimes without even meaning to.

NASA elaborated on the project’s impact, writing on its Earth Observatory website: “The epic scale of the dam project is matched by the level of controversy it continues to generate.

“Concerns about major environmental impacts, the relocation of 1.2 million people, and the flooding of 13 cities, more than 1300 villages, archeological locations, and hazardous waste dumps were raised throughout the planning and implementation.”

They added: “Environmental concerns include increased seismicity from the loading of the water, landslides, changed ecosystems, accumulated pollution, increased chances for waterborne diseases, and salinity changes in the Yangtze estuary.”

Completed in 2012, the Three Gorges Dam spans a jaw-dropping 2,335 meters in length and stands 185 meters tall.

It generates a whopping 22,500 megawatts of electricity — the same output as about 15 nuclear reactors — making it a key part of China’s push for cleaner energy and reduced carbon emissions.

In the words of Dr. Chao: “The effect is very small, but measurable.”

And sometimes, it’s those measurable moments that remind us just how powerful our presence is on this planet.

Featured image credit: Credit: VCG / Getty