Scientists warn of shortest days ever as Earth spins faster

Scientists warn that in the coming days, Earth may experience the shortest day in recorded history. Astrophysicists have discovered that the planet’s rotation speed has been increasing over the past five years.

Since 2020, Earth has been spinning faster on its axis, causing the length of a day to gradually decrease. This year, a day shorter than the usual 24 hours could occur, possibly in July or August.

Astrophysicist Graham Jones has identified three potential dates for this phenomenon: July 9, July 22, and August 5, 2025. These shorter days, estimated to be about 1.66 milliseconds less than a standard day, are believed to be influenced by the Moon’s orbit.

A standard solar day is exactly 86,400 seconds (24 hours), but Earth’s rotation has never been perfectly stable. Research shows that since 2020, Earth has been rotating faster for reasons yet unknown, resulting in shorter days.

In 2021, one day was recorded as 1.47 milliseconds shorter than usual. This shortened further to 1.59 milliseconds in 2022, and on July 5, 2024, a new record was set with the day being 1.66 milliseconds shorter than normal.

Scientists explain that the Moon’s gravitational pull affects Earth’s rotation. The upcoming dates in July and August correspond with times when the Moon is farthest from Earth’s equator, reducing its slowing effect and allowing Earth’s rotation to speed up slightly.

Over billions of years, the Moon’s gravity has gradually slowed Earth’s rotation—from days lasting just 3 to 6 hours around 4.5 billion years ago to the current 24-hour cycle.

Though a difference of a few milliseconds doesn’t impact daily life, it is important for technology and telecommunications, where precise timing is critical. If this trend continues, Earth’s rotation could eventually synchronize with the Moon’s orbit in about 50 billion years, causing one side of Earth to permanently face the Moon—similar to how the Moon always shows one face to Earth. By then, Earth’s conditions would be very different.