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Comment by bilsbie | Hacker News Reader

Can anyone explain what the alternative is? Surely we won’t just get more and more out of synch with the earths orbit?

Also why does it say the earth is slowing down but this year it sped up. Sounds quite impossible?

The slowdown is the long-term trend caused by drag of the Moon's gravity, but the speedups are sporadic and as a result of events such as massive earthquakes that cause the Earth's rotation to speed up as some significant mass falls further to the Earth's center. The conservation of angular momentum is the principle that leads to those brief speed ups, but they will not fully counteract the longterm drag caused by the Moon.

Edit: TLDR; Local maxima vs. overall trend.

>Surely we won’t just get more and more out of synch with the earths orbit?

Why does being out of sync with the Earth's orbit matter?

Because humans use time as an indicator for day and night

Also, historically, we did care about the equinoxes and solstices falling on specific days of the calendar.

We may not care anymore, but emphasis on may.

And you can still use UTC as your indicator for day and night. In 100 years, it would only drift around 1 minute.

We don't really do that on a second accuracy though. We need to add a whole new day to the calendar every four years to make up the difference. Meanwhile we've added less than half a minute worth of leap seconds.

We already accept an error of half an hour (most timezone offsets are multiples of a whole hour) or more (many timezone boundaries are widened to align with state or country boundaries). A couple of minutes is nothing next to that, and if start getting too far, we can simply redefine the timezone offsets (which we already do twice a year in many places, and any device which might be moved across timezone boundaries already have to deal with that).

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