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Time Lords decree an end to leap seconds before risky attempt to reverse time

Remember that one time the Linux kernel couldn't cope for a moment? That sort of thing should be behind us now

The Bureau International des Poids et Mesures (BIPM) has made a decision, and declared that the world can do without leap seconds.

Leap seconds have occasionally been added to official timekeeping records to reflect changes in the Earth's angular rotation and a way of measuring time called UT1.

While UT1 is valid and correct, the world also measures time using Coordinated Universal Time (UTC) – a time scale produced by BIPM.

Adding leap seconds to satisfy UT1 messes with UTC, and that makes time's overseers unhappy.

Leap seconds are also painful to promulgate in the digital realm. The Linux kernel's inability to handle added leap seconds caused plenty of crashes in 2012. A 2015 leap second also caused issues and in 2016 Cloudflare stumbled when confronted with the need to add a second.

Doing away with leap seconds has therefore been up for debate since at least 2013, on grounds that they're more trouble than they're worth and represent risks to important communications and computing systems.

Even Meta agrees with that argument, and earlier this year added its voice to calls for their demise.

Last week, the BIPM's 27th General Conference on Weights and Measures decided [PDF] the leap second's day is done.

The reasons behind the decision include that Earth's rotation has changed and we may need to insert a negative leap second – a reversal of time that has never been tried. The BIPM also revisited arguments that, as there is no standard way to handle the introduction of leap seconds, they create risks to telecommunications systems and the global positioning system.

The body therefore called for an end to leap seconds and for work to commence on a proposal for a "new maximum value for the difference (UT1-UTC) that will ensure the continuity of UTC for at least a century."

A 2035 deadline for formulating that maximum value was set, and the 28th General Conference on Weights and Measures in 2026 will vote on a resolution to make it happen.

All of which will hopefully satisfy time lords and techies alike.

Many, many, years would need to pass for this decision to become problematic, although there have been moments in history when calendars were badly out of synch with the seasons. One of Julius Ceasar's key reforms was to change the Roman calendar so that occasional insertions of extra months were no longer necessary to allow accurate timekeeping. ®

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