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Extra Leap Second To Be Added To Clocks On June 30
hcs_$reboot writes: On June 30 this year, the day will last a tad longer — one second longer, to be precise — as a leap second is to be added to clocks worldwide. The time UTC will go from 23:59:59 to 23:59:60 in order to cope with Earth's rotation slowing down a bit. So, what do you intend to do during that extra second added to that day? Well, you may want to fix your systems. The last time a leap second was added, in 2012, a number of websites, Java and even Linux experienced some troubles. Leap seconds can be disruptive to precision systems used for navigation and communication. Is there a better way of dealing with the need for leap seconds?
A recent draft of the set of options which will be presented when the World Radio Conference votes this fall is visible at http://acma.gov.au/Industry/Sp... This draft has options A, B, and C, but it is likely to be wordsmithed a lot before it is finished.
And then over time the astronomical meaning of how we keep time goes astray.
AM and PM mean "anti-meridian" and "post-meridian", and at noon on the day of the summer solstice, the sun should sit on the celestial meridian.
I'm pretty sure if we did it your way, eventually the meridian (which is how we derived both navigation and time keeping) would move around, and eventually noon would be in the middle of the night.
This stuff isn't arbitrary, it's actually based in something.
The whole point of the leap second (etc) is to keep those things lined up. Otherwise there is no way we could keep track of things like sunrise and sunset, or when you might see a specific star.
Lost at C:>. Found at C.
What you're suggesting is a variable length second. That's what GMT was before the current UTC came along. The slowdown of Earth's rotation is NOT a known factor, it varies. Things like earthquakes can change the period unpredictably.
Modern UTC ticks at a predictable rate, which is useful for some sciences. Leap seconds keep it in sync with the Earth's rotation, which is useful for others. UTC with leap seconds was deliberately intended to bridge those two needs.
If someone wants a time scale without leap seconds they shouldn't be using UTC, there are others to choose from, such as TAI or GPS.
"National Security is the chief cause of national insecurity." - Celine's First Law
No, the Earth really is slowing down very, very gradually. The tidal forces from the moon is slowly leeching off rotational energy from the Earch (as heat). See here: http://en.wikipedia.org/wiki/T...
...a better way of dealing with the need for leap seconds?"
Well... It could be worse. The last time we let the clocks go off we lost almost two weeks trying to fix it.
Let's just keep up with the leap seconds so that nobody has to cancel Christmas again.
I think your use of DST was wrong, I think you meant timezones.
Timezones break local noon/midnight by offsetting the location to an approximate less than a half-hour away, but since timezones are calcuated based on the arbitrarily-picked Greenwich, UK, really the entire planet is running on Greenwich time, with a particular significant digit adjusted to reflect distance, to approximate the natural time of the area.
Do not look into laser with remaining eye.
That POS real-time clock mechanism in your average PC holds time as good as a $10 wristwatch
NTP can keep time to within tens to hundreds of milliseconds across the public internet. Plenty good enough for 99.9999% of the applications out there. The RTC only comes into play across reboots. Even Windows has implemented NTP (albeit a crappy implementation that's "only" good to within a second or two) by default for more than a decade now.
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
> AM and PM mean "anti-meridian" and "post-meridian",
Total nitpick, its ante not anti.
ante- prefix meaning before
anti - prefix meaning against
You see it in words like "antediluvian" (before the flood).
"I opened my eyes, and everything went dark again"
And countless times I see people assume that traditional latin and/or greek roots of terms must be taken literally and dictate how they are to be used in modern times...
Numerous national standards define midnight as 12:00 AM or 0:00 AM, and noon as 12:00 PM. But many also recommend the written usage of "12 noon" and "12 midnight" to make things clear to those that don't understand AM and PM.
arbitrarily-picked Greenwich, UK,
Greenwich wasn't arbitrarily picked. The only options were Paris, Berlin, London and Washington DC -- they had the necessary observatories. London was already in widest common use, and the anti-meridian falls in a convenient place (not crossing anywhere important).