Thread · HN Continuity

An interesting project, that buries the lede to another interesting thing: abolishment of the leap second.

> In November 2022, the General Conference on Weights and Measures decided to abolish the leap second by 2035

I think the story goes that when the leap second was standardized in 1987, the wold was much less connected, there were fewer systems, and hence it was practical to keep astronomical time and civil time coordinated.

But this causes so many bugs and difficulties in practice that companies like Google don't perform leap seconds, they do leap second "smearing". But even smearing has issues, since there are multiple algorithms.

Even worse, the Earth sometimes accelerates, and there was a prospect that we might need a negative leap second, which has never been put into practice.

And as daylight savings makes everyone painfully aware, the public can tolerate even hours of misalignment between civil time and astronomical time, and even an hour adjustment.

So if we decide that we can tolerate a whole minute of skew, we need no leap minute for 50-100 years. And if we could tolerate an hour of skew, we'd not need a leap hour for millennia.

Of course, this is all can-kicking. If a leap second is difficult in practice, a leap hour in UTC (not a flip between a daylight savings and standard time zone) would be even more difficult. I feel the eventual solution would be to very slightly adjust the civil second to be shorter, so that the error begins to reduce.