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Why the U.S. Wants To End the Link Between Time and Sun

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Re: Why the U.S. Wants To End the Link Between Time and Sun

#11

Post by sonnekki »

Leap seconds are a work-around to make the 24-hour clock keep time correctly. The reason so many problems occurred was a combination of insufficient programming, but also the affect an inaccurate system.

I'm not sure what a correct system should be, but I know that it can't be based on the Earth, the sun, or any one galaxy. In order to have accurate time, it must be external to all of these things, like a meter stick is to an object.

The possible problem with this is that there will come a time when "3:00 pm" is in the middle of the night, the time to wake up for work will always "change".

edit: more thoughts

Re: Why the U.S. Wants To End the Link Between Time and Sun

#12

Post by wmf »

wl wrote: post #10
jackta101 wrote: post #2

This article is 7 years old and irrelevant. In fact a leap second was insert in June this year.

It may be seven years old, but it's not irrelevant. People are still discussing this proposal. The article is the best explanation I've seen of this issue to date. Here's a more recent article posted here a few months ago: http://www.nytimes.com/2012/01/19/science/to-keep-or-kill-lo... Personally, I wish people would just leave UTC alone. If you don't want to deal with leap seconds, use TAI, which was intended for su…

UTC and TAI are off by over 30 seconds; people can't accept a discontinuity during the switchover. So what we really want is something like TAI-35. But the real problem is coordinating everyone to switch timescales so we don't end up with half the world on UTC and half on TAI-35. Also, I've heard there are cases where people feel that they're legally obliged to use UTC because that's the legal definition of civil time.

Re: Why the U.S. Wants To End the Link Between Time and Sun

#13

Post by sonnekki »

freehunter wrote: post #9

I fail to see how this is an attack on science or on Europe. That's just hyperbole. Making time consistent to prevent having to add time or remove time just makes sense. Time is a unit of measurement. We don't redefine the foot just because the new king has 10" feet instead of 12" feet. Time being connected to the sun is a relic of the days before accurate time-keeping methods. One day should always be one day. To re…

> Noon should always be noon

In other words, given a point on Earth (or any planet) and it's angle relative to the sun it orbits, when that point aligns exactly with and faces the center of the sun, it is noon.

Consider this: The way everyone refers to time is "X Units before noon", much like the 24-hour clock (no am/pm), except 0 is noon. The key is that X must be flexible, it should have no maximum, and no minimum.

edit: clarification

Re: Why the U.S. Wants To End the Link Between Time and Sun

#14

Post by draz »

sonnekki wrote: post #13
freehunter wrote: post #9

I fail to see how this is an attack on science or on Europe. That's just hyperbole. Making time consistent to prevent having to add time or remove time just makes sense. Time is a unit of measurement. We don't redefine the foot just because the new king has 10" feet instead of 12" feet. Time being connected to the sun is a relic of the days before accurate time-keeping methods. One day should always be one day. To re…

> Noon should always be noon In other words, given a point on Earth (or any planet) and it's angle relative to the sun it orbits, when that point aligns exactly with and faces the center of the sun, it is noon. Consider this: The way everyone refers to time is "X Units before noon", much like the 24-hour clock (no am/pm), except 0 is noon. The key is that X must be flexible, it should have no maximum, and no minimum.…

reminds me of "relative time" Jews and Muslims (and Japanese, until 1872) use. This is a French wikipedia article I stumbled upon: http://fr.wikipedia.org/wiki/Shaot_zmaniot

Re: Why the U.S. Wants To End the Link Between Time and Sun

#15

Post by adjwilli »

I was hoping this was a more radical proposal like http://en.wikipedia.org/wiki/Swatch_Internet_Time was.

Our current way of measuring time is absurd. It starts as base 1000 with milliseconds, then base 60 with seconds and minutes, then 24 for hours, 7 for days, 4.3whatever for months or 28-31 however you want to track it.

I like that China only has one time zone for the entire country. We should all go by UTC times regardless of our geographical position. But we should also change our means of measuring time to work around whole base 10 numbers.

Re: Why the U.S. Wants To End the Link Between Time and Sun

#16

Post by patheman »

sonnekki wrote: post #11

Leap seconds are a work-around to make the 24-hour clock keep time correctly. The reason so many problems occurred was a combination of insufficient programming, but also the affect an inaccurate system. I'm not sure what a correct system should be, but I know that it can't be based on the Earth, the sun, or any one galaxy. In order to have accurate time, it must be external to all of these things, like a meter stick…

"3:00 pm" is in the middle of the night, the time to wake up for work will always "change"..

well, one time .. but do you !really! care about how the folks in +600 yrs measure time? I'd guess they invent some kind of "glacial-period-light-saving-time" by then...

Re: Why the U.S. Wants To End the Link Between Time and Sun

#17

Post by mdonahoe »

I was expecting something more like Swatch Internet time. http://en.m.wikipedia.org/wiki/Swatch_Internet_Time

Why must time be be earth centric? Imagine how hard it must have been for Copernicus to convince everyone to use his model. Lazy programmers isn't as compelling argument, but it has similarities. http://en.m.wikipedia.org/wiki/Copernican_Revolution

Non-rhetorical questions: Does the Mars Curiousity rover use leap seconds? Does it have Martian time too?

Re: Why the U.S. Wants To End the Link Between Time and Sun

#18

Post by wl »

wmf wrote: post #12
wl wrote: post #10

Earlier quoted context omitted.

It may be seven years old, but it's not irrelevant. People are still discussing this proposal. The article is the best explanation I've seen of this issue to date. Here's a more recent article posted here a few months ago: http://www.nytimes.com/2012/01/19/science/to-keep-or-kill-lo... Personally, I wish people would just leave UTC alone. If you don't want to deal with leap seconds, use TAI, which was intended for su…

UTC and TAI are off by over 30 seconds; people can't accept a discontinuity during the switchover. So what we really want is something like TAI-35. But the real problem is coordinating everyone to switch timescales so we don't end up with half the world on UTC and half on TAI-35. Also, I've heard there are cases where people feel that they're legally obliged to use UTC because that's the legal definition of civil tim…

TAI for the timekeepers and as an internal representation, UTC for display, much like how many computers keep time in UTC and apply an offset to display local time. Just because we have to deal with the legacy of POSIX doesn't mean this isn't the right solution.

Yes, there are the obvious problems like the uncertainty of scheduling future events in UTC because the insertion of leap seconds aren't known in advance. But such things should be scheduled in TAI, anyway.

Re: Why the U.S. Wants To End the Link Between Time and Sun

#19

Post by lutusp »

freehunter wrote: post #9

I fail to see how this is an attack on science or on Europe. That's just hyperbole. Making time consistent to prevent having to add time or remove time just makes sense. Time is a unit of measurement. We don't redefine the foot just because the new king has 10" feet instead of 12" feet. Time being connected to the sun is a relic of the days before accurate time-keeping methods. One day should always be one day. To re…

> I suppose one could say that noon should always be noon ...

Yes, but by allowing our clocks to go out of sync with the natural time of noon, a relationship controlled by orbits rather than clocks, this proposal would prevent that. Over time noon (highest solar position in the local sky) would drift away from noon as given by a clock.

I especially like the part where this proposal's advocates dismiss those who use a sextant to locate themselves on the ocean. I personally required this clock consistency to navigate my boat during my around-the-world sail, after my hi-tech satellite receiver expired.

This is not to argue that there's only one good argument here -- both arguments are reasonable. Unfortunately, they differ in the most basic way.

If we stick to 86,400 seconds in a day and don't allow leap-seconds, eventually daylight will happen at midnight -- either that or we will require leap-hours or even leap-days (as happened in Europe during the transition from the Julian to the Gregorian calendars).

If we continue to allow leap-seconds, all sorts of chronological record-keeping will continue to be more complex than it needs to be.

As with all truly interesting problems, there's no easy answer.

Re: Why the U.S. Wants To End the Link Between Time and Sun

#20

Post by 001sky »

ilcavero wrote: post #6
001sky wrote: post #3

But adding these ad hoc "leap seconds" -- the last one was tacked on in 1998 -- can be a big hassle for computers operating with software programs that never allowed for a 61-second minute, leading to glitches when the extra second passes. "It's a huge deal," said John Yuzdepski, an executive at Symmetricom Inc., of San Jose, Calif., which makes ultraprecise clocks for telecommunications, space and military use... Is…

you are wrong in your rationale because crappy programming cannot be fixed and together with the current time definition it causes big problems to many, on the other hand changing the time definition causes problems to whom? astronomy purists?

What are your definitions of "cannot be fixed" "Many" and "Problems"? Biological clocks and cellular metabolism are tied to daylight, amongst other things. Talk about programming that cannot be fixed! Does that make 6 billion astronomy purists ;) ?

Edited: For levity

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