VERSAILLES, France, Oct. 15, 2026 - The world's timekeepers voted on 15 October to end the leap second.^[1] Under Resolution 5, adopted at the 28th General Conference on Weights and Measures (CGPM) in Versailles,^[2] Coordinated Universal Time (UTC) will run on without leap-second jumps^[3] from 20 May 2027.^[4] Since 1972, leap seconds have kept atomic UTC in step with UT1, the time set by Earth's rotation,^[5] and 27 were added between 1972 and 2016.^[6] From now on the two may drift up to one hour apart before any correction.^[7] Scientists expect such a "leap hour" will not be needed for more than 1,000 years,^[8] and timeanddate.com reports that no correction should be needed for several thousand years.^[9] The change comes as Earth's rotation has sped up in recent years.^[10] Under the old rules there was a 30% chance that the first-ever negative leap second would be needed within 10 years,^[11] and removing a second could disrupt digital infrastructure.^[12] The conference also looked beyond Earth. Resolution 6 addresses an international time scale for the Moon^[13] and encourages space agencies to share their lunar timekeeping experience.^[14] Resolution 4 lays the groundwork for a new definition of the second, to be adopted in 2030.^[15] Impact Insight. Atomic clocks count the steady vibrations of atoms, while Earth's spin speeds up and slows down with tides, winds and shifts deep inside the planet, so the two kinds of time slowly drift apart. Precise time matters for planetary defense: predicting where an asteroid will be, and pointing radars and telescopes at it, depends on knowing both atomic time and Earth's exact orientation, so astronomers will keep tracking Earth's rotation closely even after civil clocks stop jumping.