alt Hacker NewsIn short, yes, the weather, geology, and signicantly, human movement of water via aquifer draining and dam building, as well as glaicial and ice melts, all contribute to unpredictable changes in the earths rotational period, as well as the axis of rotation. The models for this are IIRC trigonometric polynomials of fairly low order, so even if we could model the unpredictability perfectly, truncation error would limit our ability to distribute the model at super high accuracy. The existing models are built in to, eg, satellites, so you can't just make them arbitrarily complex.
Fun fact: leap seconds will stop being a thing soonish. I think they phase out in 2035, with a delay because Russia needed time to update glonass satellites.
(Note: on mobile, this is from memory, details need checking ;))
Replies
> because Russia needed time to update glonass satellites.
Why is this? As leap seconds don’t occur on a regular frequency, I assume they are not hardcoded on the software or hardware on board, but the control centre uploads them on the satellites enough in advance once they have been scheduled. So why can’t the control centre just stop sending those updates?
> as well as the axis of rotation
A frightening fact, the 2011 magnitude 9.0 Tohoku Earthquake shifted the position of the Earth's figure axis about 17 centimeters, making days about 1.8 microseconds shorter.
> Russia needed time to update glassnoss satellites
GLONASS maybe? or really glasnost era satellites?
A butterfly flaps its wings in Tokyo and we lose a leap second.
2035 is the agreed drop dead date.
Everybody agreed that "Leap seconds" are a sufficiently bad idea that they should be replaced by 2035. Nobody has agreed how to fix it, and "Just turn them off" isn't technically legal. However, "What if there were Leap hours instead?" is technically legal and of course those hours would happen in the very distant future (likely after our civilisation is gone) so it's functionally identical to "Just turn them off" but without legal problems.
Now, I'm English, and England loves this sort of hack. You may have heard that controversial UK politician Nigel Farage "resigned" as a Westminster MP recently and that's not technically true because you can't resign, historically people hated that job and so you can't resign and we never changed that, but what you can do, and everybody does, is get assigned an "Office of profit" in which legally the King is paying you, an MP can't work for the King so you can't be an MP any more. The "Offices of profit" in question aren't real jobs† and don't pay real money, like this "Leap Hour" they'd be a legal fiction. So everybody says you "resigned" but in fact you legally can't do that...
† I mean, historically they were real jobs that made sense which is why the King paid somebody to do them, but England is very, very old so they haven't made sense for centuries and serve only as a legal fiction today.