Every second counts in a high-paced, high-tech world. Except when it shouldn’t.
The 28th General Conference on Weights and Measures (CGPM) in Versailles in October is expected to settle a debate over whether we should be so pedantic about our measures of time, putting the future of the leap second to a vote.
If the members’ opinions are any indication, coordinated universal time (UTC) will be adjusted by adding an hour as needed, rather than tweaking time by nickel-and-diming it each year.
Fundamentally, our planet’s spin is the problem. It’s just not as consistent as we’d like. With melting ice, shifting wind patterns, and changing tidal forces redistributing Earth’s angular momentum, our planet’s rotation can change speed by more than a second each year.
This won’t affect your beauty sleep, but if left unchecked, it just might confuse global systems that coordinate their actions with split-second precision based on the rapid-fire tick-tock of super-precise atomic clocks. So in 1972, the International Bureau of Weights and Measures introduced the leap second – an extra moment intended to keep UTC in line with Earth’s slightly longer days.
In total, 27 leap seconds have been wedged into the calendar to account for Earth’s longer days, the last being in 2016.
Then, in 2020, Earth started to pick up speed again. Not by much, but it was enough to raise the question of whether we might need to consider cutting a second from the year in a decade or so instead.
It’s far from a trivial suggestion. Leap seconds have cost companies in the past, grounding flights and causing networks to glitch. A negative leap second would be new territory and unlikely to be risk-free, especially given that few modern computing systems were designed with this kind of time debt in mind.
Four years ago, CGPM members saw the writing on the wall and realized the frequent, tiny adjustments to time were more of a headache than they were worth.
Instead, why not just wait until the discrepancy grows big enough to be a real problem?
This isn’t as irresponsible as it sounds. Many tech companies, like Google, have their own fix to the millisecond problem, such as by stretching some seconds out slightly rather than shoving it all inside a single quantum leap.
By waiting until UTC and the planet’s spin disagree by as much as an hour, the official ledgers can be adjusted far less often. A leap hour would only need adding every few centuries.
Though if this is the plan of attack, it ought to be decided sooner rather than later.
We’ll find out soon, though. If enough members vote in favour of the draft proposal, the count for a leap hour would start from May 20 next year.
We can’t wait.
Source: Financial Times
