Mysterious boost to Earth's spin will make Aug. 5 one of the shortest days on record

image via Space.com

August 4, 2025, 10:00 AM

• •Earth's rotation has sped up in recent years, making days slightly shorter.
• •Scientists are puzzled by this trend after decades of slowing down.
• •The moon's position and declination influence tidal forces affecting Earth's rotation.
• •The liquid core's slower rotation may be the underlying cause of the acceleration.
• •A negative leap second could be added if the situation continues through 2029.

Earth's days are becoming milliseconds shorter due to a change in its rotation speed, a trend that has scientists puzzled. After years of slowing down, the planet's rotation has unexpectedly sped up, leading to shorter solar days. The moon's position influences tidal forces and subtly affects Earth's rotation rate, causing short-term fluctuations. The underlying cause of the acceleration may be the slower rotation of Earth's liquid core.

Read original article