When the moon is positioned farther from Earth's equator and closer to the poles, its pull on the planet becomes weaker. With less resistance, Earth is able to spin a bit faster, which makes the day slightly shorter than usual.

Scientists expect a specific day in July to be the shortest day of 2025 so far, running just over a millisecond faster than the standard 24-hour cycle.

Earth is set to break records with July 9 marking the shortest day ever recorded, shaving off 1.3–1.5 milliseconds due to lunar orbit shifts

July 9 was unusually short thanks to changes in how fast the Earth is spinning. But two other days this summer are expected to be even shorter.

July 9 was predicted to have a shorter "length of day" than usual due to an increase in Earth's rotation speed. See which other days will be shorter

The 24-hour day isn’t a given anymore. In recent years, scientists have discovered Earth is rotating slightly faster, which means slightly shorter days. Wednesday, in fact, was one of the shortest days in history — 1.

Earth’s rotation is speeding up. This summer, our planet will spin faster than usual, creating the shortest day since records began. Though we cannot sense these changes, they show the forces that reshape our world.