Earth's Speeding Up! Is Today Shorter Than You Think?

Feeling like today is flying by? You might be right! Scientists are tracking a slight increase in Earth's rotation speed, making some days a tiny bit shorter than the standard 24 hours. While you won't notice the difference without precise instruments, this phenomenon is part of an intriguing trend that has experts buzzing.

Earth's Rotation: A Variable Phenomenon

The International Earth Rotation and Reference Systems Service predicts that July 22nd will be a millisecond shorter than normal. This isn't unusual, as variations in Earth's rotation are common. In fact, July 9th saw the Earth's spin shorten the day by nearly 1.4 milliseconds. But the recent buzz around "freakishly short" days in July and August has captured public attention.

Why is Earth Speeding Up (and Slowing Down)?

Several factors influence Earth's rotation, including the gravitational pull of the moon, atmospheric winds, and the movements within the Earth's liquid core. Dennis McCarthy, a time expert at the U.S. Naval Observatory, explains that these variations have been observed for over a century. Historically, the moon's tidal friction has gradually slowed Earth's rotation, lengthening days. However, recent data shows a reverse trend.

Since 2020, Earth has been breaking its own speed records. The shortest day ever measured occurred on July 5, 2024, clocking in at 1.66 milliseconds faster than usual. July 10th, 2025, became the shortest day so far this year at 1.36 milliseconds less than 24 hours. July 22nd is expected to be close behind at 1.34 milliseconds less.

If this trend continues, scientists may need to subtract a "negative leap second" from atomic clocks around 2029 – a first in history. While the change is imperceptible to us, it highlights the dynamic nature of our planet's rotation.