The General Conference on Weights and Measures is expected to approve a proposal to end leap seconds, according to The Register. The change, effective May 20, 2027, would widen the permitted gap between Coordinated Universal Time (UTC) and the astronomical time scale UT1 from 0.9 seconds to one hour. That would keep UTC continuous for centuries without the periodic adjustments that have been made since 1972.
Leap seconds have long been a headache for networked systems, because inserting an extra second can cause timing discrepancies across infrastructure such as mobile networks and power grids. The risk is growing: Earth's rotation has recently sped up, and experts estimate a 30 percent chance that a negative leap second—removing a second rather than adding one—would be needed by 2035. Many computer systems are designed to handle added seconds but not removed ones.
Setnam Shemar of the UK's National Physical Laboratory said the proposal would avoid leap-second risks for centuries. He noted that the link between UTC and UT1 would not be severed: UT1 would still be monitored, and the difference between the two scales would continue to be published through international services. With broad national support, the measure is expected to pass. The Register notes that the decision affects astronomy and celestial navigation, which rely on the relationship between UTC and UT1, but those fields would still have access to the data they need.