🌅 The Earth Is Spinning Faster than Usual

SOURCE

James O'Donoghue (2025)

WHAT TO KNOW

• The Earth completed a full rotation in just 86,399.99867 seconds on Tuesday, August 5, making it one of the shortest days of the year. That’s 1.33 milliseconds faster than our planet’s typical rotation, which clocks in at an average time of 23 hours, 56 minutes, 4 seconds, and 90.5 milliseconds.

WHY IT MATTERS

• Experts say three primary factors impact the Earth’s rotation: the core, the atmosphere, and the Moon. The planet’s solid inner core—which spins independently of the molten outer layers—has slowed over the past 50 years as part of a natural cycle, causing the outer layers to speed up to counteract the momentum loss. Seasonal jet streams have also changed the speed of winds in both hemispheres, which forces the Earth to spin faster to compensate. Finally, the impact of the Moon’s gravity on our oceans forces water to shift, causing an infinitesimal amount of friction between the ocean and the seafloor, which, at geologic timescales, slows the planet’s rotation.

CONNECT THE DOTS

• The Earth’s rotation impacts the keeping of time, which is based on more than 400 atomic clocks located around the world that rely on incredible levels of accuracy for precise measurement. Banks, computers, financial systems, telescopes, and electricity networks across the globe all rely on highly accurate synchronization to operate, meaning milliseconds indeed matter.