Shorter days ahead? Earth's rotation is speeding up, warn scientists
This might sound strange, but Earth's rotation has always changed over long periods. Dinosaurs, for example, lived with 23-hour days. And in the Bronze Age, the average day was already about half a second shorter than today's standard. Looking ahead, scientists predict that 200 million years from now, one Earth day will last about 25 hours.
Why is the Earth spinning faster?
Normally, a day lasts 24 hours, or 86,400 seconds. But that's not completely accurate.
Many things—like earthquakes, volcanic activity, ocean tides, and even underground changes—can make the planet spin slightly faster or slower. Even though the overall trend has been for Earth to slow down, something unusual has been happening since 2020.
According to the International Earth Rotation and Reference Systems Service (IERS), based in Washington D.C., the Earth's rotation has started to speed up. This has been happening steadily enough that experts now believe we may need to remove a leap second from our clocks in 2029—the first time this has ever happened.
A recent report from timeanddate.com says that this trend will continue into 2025. Based on current data, the three shortest days of the year will be July 9, July 22, and August 5. The shortest of all, August 5, is expected to be about 1.51 milliseconds shorter than the usual 24 hours.
What's causing it?
This unexpected speed-up has puzzled experts. Leonid Zotov, a rotation researcher at Moscow State University, told timeanddate.com, 'Nobody expected this.'
Zotov helped write a 2022 study trying to figure out the cause, but he says that so far, no model fully explains it.
Most scientists believe the answer lies deep inside the Earth—possibly something happening in the core. Ocean and atmosphere changes don't seem to account for the speed increase.
While this spinning trend might continue for now, it's not a sign that we're heading back to dinosaur-era days. Earth's long-term natural tendency is still to slow down over time. Things like melting ice at the poles and surface changes can also affect this.
So, while we might 'lose' a leap second soon, Earth isn't going off track—just reminding us that even time isn't perfectly steady.
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United News of India
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- United News of India
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NDTV
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- NDTV
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Earth is spinning faster and scientists fear a Y2K-like Doomsday
Earth is spinning faster than usual this summer, raising concerns among scientists about potential disruptions to global timekeeping systems — with fears reminiscent of the Y2K scare . According to a CNN report citing data from the International Earth Rotation and Reference Systems Service and the US Naval Observatory, July 10 was the shortest day of the year so far, clocking in 1.36 milliseconds under the standard 24 hours. More short days are expected on July 22 and August 5. The Earth's rotation isn't perfectly consistent. Factors like lunar gravitational pull, seasonal atmospheric shifts, and the motion of the planet's liquid core cause slight variations in the length of a day. While the changes are typically imperceptible in daily life, even millisecond discrepancies can affect technologies that rely on hyper-accurate timing — such as telecommunications, satellite systems, and financial networks. Explore courses from Top Institutes in Please select course: Select a Course Category Data Analytics healthcare Technology Finance Project Management Data Science Management Public Policy others Design Thinking Data Science Healthcare Leadership Artificial Intelligence Others Digital Marketing Product Management Cybersecurity PGDM Degree CXO MBA MCA Operations Management Skills you'll gain: Data Analysis & Visualization Predictive Analytics & Machine Learning Business Intelligence & Data-Driven Decision Making Analytics Strategy & Implementation Duration: 12 Weeks Indian School of Business Applied Business Analytics Starts on Jun 13, 2024 Get Details To maintain precise time, atomic clocks — which have been used since 1955 — track time to an extraordinary level of accuracy. Coordinated Universal Time (UTC), used worldwide, is based on atomic clocks. If Earth's rotation falls out of sync with UTC, leap seconds are added to bring them back into alignment — a process that's occurred 27 times since 1972. However, as Earth's spin has been accelerating, no leap second has been added since 2016. Scientists are now warning that a negative leap second — subtracting a second instead of adding one — may be required as early as 2035. 'There's never been a negative leap second,' physicist Judah Levine told CNN, but the chances of it happening are now around 40%. Such a move could wreak havoc, especially since many systems still struggle with positive leap seconds even after five decades. A negative leap second, never before implemented, could cause failures across systems that depend on stable, continuous time — evoking comparisons to the Y2K bug. Interestingly, climate change may be buying time. The CNN article, citing a study published last year by Agnew in the journal Nature, claimed that melting ice in Greenland and Antarctica is redistributing mass across the planet, subtly slowing Earth's spin and counteracting the speed-up. Live Events Benedikt Soja, an assistant professor at The Swiss Federal Institute of Technology in Zurich, Switzerland, told CNN that if warming continues, "the effect of climate change could surpass the effect of the moon, which has been really driving Earth's rotation for the past few billions of years.' 'I think the (faster spinning) is still within reasonable boundaries, so it could be natural in a few years, we could see again a different situation, and long term, we could see the planet slowing down again. That would be my intuition, but you never know,' Soja added.
