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I don't even see the need for leap seconds at all (in either direction). Why should anyone care? All times are relative to some arbitrary fixed point in time an

I don't even see the need for leap seconds at all (in either direction). Why should anyone care? All times are relative to some arbitrary fixed point in time anyway, so why are we so hung up on maintaining the status quo? Aside from the fact that just by ignoring the problem it'll probably go away - we've just had a period of adding a load of leap seconds to roughly compensating for the Earth rotating "too slowly" overall, which for a system that's inherently irregular and actually speeds up and slows down all the time, and just happens to have been "too slowly" ON AVERAGE. It now seems hat the rotation speed, on average, is "too fast" and now we need to undo some of that adjustment. If we'd just left it alone, it'd have been fine. And for all the hassle these leap seconds cause, what exactly has been the benefit? Since 1972, we've had 27 seconds added. 27 WHOLE SECONDS. That would have made absolutely no difference to anybody's life if the sunrise and sunset was 27 seconds later. Just think, in 100 years, when your great grandchildren are enjoying their life, we might be a whole minute wrong. And if you went the other direction, back as far as all of recorded human history, and we might be out by an hour. Many of us are routinely forced to have our clocks out by an hour for "daylight savings time" every year anyway. For the very few cases where it might be useful to know the ACTUAL difference between the rotation and alignment of an abritrary fixed point on earth and an arbitrary fixed point on the sub, then THEY can use they own clock for that specialised purpose. And maintain a fixed adjustment to the atomic clock based time that everyone else uses, and they don't even have to round to a whole second for that - they can say NASA time is TAI+1.234s for instance and the only people who need know or care is NASA themselves.

Mountain_Skies 2y ago
For most civil purposes, it really doesn't matter but we're techies and it's in our nature to obsess over details like this, often to the determent of ourselves and the systems we're trying to maintain. It appears many of those with the most influence over setting the example for such things in the civil realm have indeed discovered the leap second is far more trouble than it is worth and now it is falling out of favor. For astronomical, aeronautical and other scientific purposes, they'll continue to deal with the hassles, but for the rest of us, it appears the era of leap seconds is slowly drawing to a close.
- zarzavat 2y ago
  Leap seconds are both unnecessary and useless at solving the problem they are intended to solve. If you care about the position of the sun to second precision, then time alone tells you nothing - you need location too. Ironically, most people get their location these days using GPS which is based on TAI, not UTC with leap seconds. If you don’t care about the position of the sun to second precision then leap seconds are a nuisance. There’s zero reason to have leap seconds in the definition of time. It should be a database, like tz, that software that wants Earth rotation updates for calculation of sun position can download and incorporate into its calculations for increased accuracy. The fundamental problem with leap seconds is that you can’t predict what the leap second delta between UTC (legal time) and TAI (absolute time) will be in the future. That’s unacceptable, I should be able to know how many seconds there are between 1 July 2024 and 1 July 2026 without needing to wait for a Time Lord to determine it.
  - ralferoo 2y ago
    > without needing to wait for a Time Lord to determine it. They're not to blame - Davros is responsible for the leap seconds.
  - zokier 2y ago
    > If you care about the position of the sun to second precision, then time alone tells you nothing - you need location too Unless you are using time and (celestial) observations to determine your location. It's not coincidence that US Naval Observatory (and its peers) is one of the key origins of UTC.
- School-Cotton 2y ago
  > but we're techies and it's in our nature to obsess over details like this Speak for yourself! Part of good engineering is knowing when over-engineered perfection is useless. The inventors of UTC/leap seconds did not, and made a serious mistake the rest of us have had to live with.
layer8 2y ago
A significant number of systems related to Earth’s rotation (like navigational systems) rely on the difference between UT1 and broadcast UTC to be less than 1 second. If UTC were to change to a constant offset to UT1, those systems would need to be provisioned in an alternative manner to receive a time signal with the same guarantee. Basically, we would still need what is now broadcast as UTC, just under a different name. And if we have that, we might just as well keep civil time synchronized to it. > Since 1972, we've had 27 seconds added. 27 WHOLE SECONDS. That would have made absolutely no difference to anybody's life if the sunrise and sunset was 27 seconds later. The delta increases quadratically though due to Earth’s rotation slowing down in the long term, so the problem will only get more severe.
- zokier 2y ago
  > A significant number of systems related to Earth’s rotation (like navigational systems) rely on the difference between UT1 and broadcast UTC to be less than 1 second. Can you name some of these systems?

Mountain_Skies 2y ago

For most civil purposes, it really doesn't matter but we're techies and it's in our nature to obsess over details like this, often to the determent of ourselves and the systems we're trying to maintain. It appears many of those with the most influence over setting the example for such things in the civil realm have indeed discovered the leap second is far more trouble than it is worth and now it is falling out of favor. For astronomical, aeronautical and other scientific purposes, they'll continue to deal with the hassles, but for the rest of us, it appears the era of leap seconds is slowly drawing to a close.

zarzavat 2y ago
Leap seconds are both unnecessary and useless at solving the problem they are intended to solve. If you care about the position of the sun to second precision, then time alone tells you nothing - you need location too. Ironically, most people get their location these days using GPS which is based on TAI, not UTC with leap seconds. If you don’t care about the position of the sun to second precision then leap seconds are a nuisance. There’s zero reason to have leap seconds in the definition of time. It should be a database, like tz, that software that wants Earth rotation updates for calculation of sun position can download and incorporate into its calculations for increased accuracy. The fundamental problem with leap seconds is that you can’t predict what the leap second delta between UTC (legal time) and TAI (absolute time) will be in the future. That’s unacceptable, I should be able to know how many seconds there are between 1 July 2024 and 1 July 2026 without needing to wait for a Time Lord to determine it.
- ralferoo 2y ago
  > without needing to wait for a Time Lord to determine it. They're not to blame - Davros is responsible for the leap seconds.
- zokier 2y ago
  > If you care about the position of the sun to second precision, then time alone tells you nothing - you need location too Unless you are using time and (celestial) observations to determine your location. It's not coincidence that US Naval Observatory (and its peers) is one of the key origins of UTC.
School-Cotton 2y ago
> but we're techies and it's in our nature to obsess over details like this Speak for yourself! Part of good engineering is knowing when over-engineered perfection is useless. The inventors of UTC/leap seconds did not, and made a serious mistake the rest of us have had to live with.

layer8 2y ago

A significant number of systems related to Earth’s rotation (like navigational systems) rely on the difference between UT1 and broadcast UTC to be less than 1 second. If UTC were to change to a constant offset to UT1, those systems would need to be provisioned in an alternative manner to receive a time signal with the same guarantee. Basically, we would still need what is now broadcast as UTC, just under a different name. And if we have that, we might just as well keep civil time synchronized to it. > Since 1972, we've had 27 seconds added. 27 WHOLE SECONDS. That would have made absolutely no difference to anybody's life if the sunrise and sunset was 27 seconds later. The delta increases quadratically though due to Earth’s rotation slowing down in the long term, so the problem will only get more severe.

zokier 2y ago
> A significant number of systems related to Earth’s rotation (like navigational systems) rely on the difference between UT1 and broadcast UTC to be less than 1 second. Can you name some of these systems?