---
title: "International Bureau of Weights and Measures Abolishes Leap Seconds"
url: https://newscentral.site/international-bureau-of-weights-and-measures-abolishes-leap-seconds/
language: en
publisher: "News Central Site"
section: "Science"
published: 2026-10-16T13:59:18.000Z
updated: 2026-10-18T02:40:34.485Z
id: bc0d37b0-7f2f-4216-90aa-ec2c4a1c353c
source: "New Scientist https://www.newscientist.com/article/2594285-scientists-have-just-voted-to-abolish-leap-seconds/?utm_campaign=RSS|NSNS&utm_content=home&utm_medium=RSS&utm_source=NSNS"
attribution: "Link to https://newscentral.site/international-bureau-of-weights-and-measures-abolishes-leap-seconds/ and name News Central Site when you quote or summarize this story."
---

# International Bureau of Weights and Measures Abolishes Leap Seconds

Scientists from 69 countries have approved a change to how global clocks are synchronized, effectively ending the practice of adding leap seconds.

A major shift in how we keep global clocks synchronized has been approved by scientists from 69 countries who met at the International Bureau of Weights and Measures (BIPM) in Versailles, France on October 15th.

The decision to abolish leap seconds will allow universal time to gradually drift apart from astronomical time before it is corrected. This means that the discrepancy between clock time and celestial time will grow by up to an hour before it is adjusted.

Representatives of 69 countries voted in favor of the change, effectively ending a long-standing practice that has been used since 1967 when atomic clocks became accurate enough to define a global time standard called coordinated universal time (UTC). This standard is based on the vibrations of caesium-133 atoms and is much more precise than astronomical observations.

The impact of this change will be subtle at first, but over time it will become noticeable, with some comparing it to living in a permanent state of daylight saving time.

As the Earth's rotation slows down, scientists have had to intervene by adding extra leap seconds to our timekeeping system. This has resulted in a total of twenty-seven added to UTC since their introduction in 1972.

However, this strategy is now set to be abandoned due to the increasing complexity and potential risks associated with introducing leap seconds. Technological systems such as stock markets, telecommunications, GPS, and others have become highly reliant on precise timekeeping, making it more challenging to implement these adjustments without disrupting critical services.

For instance, previous leap seconds have caused websites to crash and airlines' booking systems to be disrupted. According to experts, the integration of time into modern systems has made them increasingly vulnerable to even minor changes in timekeeping.

The Earth's rotation is also undergoing a slight acceleration, which raises the possibility of needing a "negative leap second, a first-ever occurrence that would involve moving the clock backwards by one second. This scenario highlights the need for an alternative solution to replace the traditional leap second system.

A new system has been voted in by scientists to replace traditional leap seconds, allowing UTC to diverge from astronomical time for up to an hour before being corrected.

This leap hour will ensure a continuous flow of time for several centuries, according to Dimarcq, who emphasized that the change is intended to maintain uninterrupted timekeeping. The correction process will still involve accurate tracking of Earth's rotation to provide valuable information for astronomy and celestial navigation.

The shift to a leap hour" system is set to take effect on May 20, 2027.

---
Source: [New Scientist](https://www.newscientist.com/article/2594285-scientists-have-just-voted-to-abolish-leap-seconds/?utm_campaign=RSS|NSNS&utm_content=home&utm_medium=RSS&utm_source=NSNS)  
Published by News Central Site: https://newscentral.site/international-bureau-of-weights-and-measures-abolishes-leap-seconds/