In 2027, the world’s timekeepers will implement a big change to help keep clocks and computer systems running smoothly.
The transition will take effect on May 20, 2027 (World Metrology Day). The International Bureau of Weights and Measures (BIPM) decided to stop adding the “leap seconds” that keep our time in sync with the Earth’s spinning.
Atomic clocks are incredibly accurate. They provide the standard time used around the world. (This is known as UTC, which stands for Coordinated Universal Time).
The first leap second timekeepers added to UTC in 1972 when they worried that atomic clocks and the Earth’s rotation were getting out of sync.
That’s because the Earth actually rotates at slightly different speeds on different days. The speed of the rotation depends partly on the pull of gravity from the moon on the Earth’s oceans.
The Earth’s atmosphere and even the core at the Earth’s center also affect its speed.
To keep atomic clocks in sync with the spinning of the Earth, scientists have added an extra second every few years since 1972. It’s similar to adding an extra day to the calendar (February 29) in leap years.
How Leap Seconds Cause Problems?
The extra second isn’t a big deal for most people, but it can cause real problems for computers.
Many computer systems use very precise time to store information or trigger certain actions. When a leap second is added, it can lead to trouble.
In 2012, for example, the websites for Qantas airlines and Reddit experienced major problems as the result of a leap second being added to UTC. But over time, many large tech companies figured out ways to handle leap seconds.
But recently, a new problem has come up. As the planet warms and ice melts, the Earth has been spinning faster. To keep the two times lined up, scientists may need a negative leap second in just a few years.
That would mean they would take a second away instead of adding one. Since this has never been done before, scientists worried it could cause big problems for computer systems worldwide.
So starting next year, the BIPM decided to stop using leap seconds. Instead, UTC time will drift slightly out of sync with Earth’s rotation.
Most people won’t notice anything. Clocks will keep running normally, with 60 seconds in a minute and 24 hours in a day. But for scientists who study the stars or earthquakes, things will be more complicated.
They’ll have to do some extra math to make sure their measurements are accurate as Earth’s rotation drifts away from atomic time.
Is Leap Second going to be replaced by something else?
Far in the future, the BIPM says there may be a “leap hour”. That would happen when the difference between atomic time and Earth’s rotation reaches 3,600 seconds (one hour).
But that won’t happen any time soon. Scientists say it will probably take over 3,000 years for the two time systems to drift so far apart.
Getting rid of the leap second solves the problem of the negative leap second and avoids challenging the world’s complex computer systems.
As the head of the BIPM’s time department, Patrizia Tavella, says, “The nice fact is that we have nothing to do!”
Content contributed and edited by nfk editors, Wiltshire, reported from Versailles, France, sourced by newsforkids.net