Read, Watch or Listen

Earth's rotation is speeding up slightly in early August 2025, causing days to be 1.3 to 1.51 milliseconds shorter than usual on July 9th, 22nd, and August 5th. This is due to the moon's position relative to Earth's equator. While Earth's rotation generally slows down over long periods, short-term variations occur due to factors like the moon's gravitational pull, ice movement, and seasonal changes. These variations are minor and don't affect daily life; however, the International Earth Rotation and Reference Systems Service monitors these changes and may add leap seconds to maintain synchronization between atomic clocks and Earth's rotation.

Prepared by Olivia Bennett and reviewed by editorial team.