On July 19, 2020, Earth set a new milestone by completing its daily rotation 1.47 milliseconds shorter than 86,400 seconds. This wasn’t a one-off event; the trend has continued since then.

Until 2020, the shortest "length of day" ever recorded by atomic clocks was -1.05 ms, meaning that Earth completed one daily rotation in 1.05 milliseconds less than 86,400 seconds.

Why this July day may be shortest so far in 2025 Scientists anticipate that Earth's rotation will quicken enough to create three shorter days between July and August, starting Wednesday, July 9.

Until 2020, the shortest "length of day" ever recorded by atomic clocks was -1.05 ms, meaning that Earth completed one daily rotation in 1.05 milliseconds less than 86,400 seconds.

Planetary Tailspin The Earth's rotation is about to accelerate significantly. According to scientists, July 9, July 22, and August 5 of this year will be some of the shortest days in years as a ...

Until 2020, the shortest "length of day" ever recorded by atomic clocks was -1.05 ms, meaning that Earth completed one daily rotation in 1.05 milliseconds less than 86,400 seconds.

Since then, Earth has broken that record every year by roughly half a millisecond. The shortest day on record was July 5, 2024, when Earth completed its rotation 1.66 milliseconds faster than normal.

Until 2020, the shortest "length of day" ever recorded by atomic clocks was -1.05 ms, meaning that Earth completed one daily rotation in 1.05 milliseconds less than 86,400 seconds.

On these days the Earth will be measurably—and, so far, unaccountably— accelerating its rotation, shaving from 1.3 to 1.5 milliseconds off of the usual 24 hours the typical day gets.

Earth's rotation is speeding up today for the 3rd and final time this summer Aug. 5 will be one of the shortest days of the year — by 1.25 milliseconds. Kate Murphy, Reporter ...