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US DoD Poll On Leap Seconds
@10u8 writes "For time scales to leap, or not to leap, has been the question here before. The ITU-R will be considering leap seconds again in a few weeks. This week the USNO posted a survey about leap seconds by the US DoD. The issue has civil implications as well as technical ones, and there is a demonstrated way to respect the history, remove leaps from navigation and POSIX time, yet keep the sun overhead at noon."
Why would you want to get rid daylight savings time? I would make the argument that we should extend it even more. I can't stand leaving for work when it's still dark, and getting off when the sun is starting to go down. My skin is already turning incandescent green from spending too much time in the office.
Think of how many lives daylight savings saves regarding traffic
Why would you want to get rid daylight savings time?
Because it is like cutting a foot off of one end of a blanket and sewing it on the other end and expecting to get a blanket that is a foot longer. Kind of dumb. If you want to get up when it is light, get up earlier. When should we all have to move the clock back and forth? Split the difference between DST and normal time and leave it. Who cares if the sun isn't overhead at exactly noon.
If you're going to do this sort of thing - adding seconds to the clock here or there - it shouldn't be decided upon by some review committee. There should be a planned algorithm that kicks in, and the simplest one that actually does the job should be used. The bottom line is that a watch should be able to do it. If you do this, you're able to program devices to account for leap seconds instead of having to manually put in fudges which is an error prone process. You also get the possibility of adding leap milli-seconds or micro-seconds so fine grained adjustments are possible where required, whereas it would be much harder (though not impossible) to do that if you're manually correcting.
It cannot be done. Leap seconds are dependent on unpredictable, chaotic natural events -- namely the fact that one day in not exactly 24 hours in length. The daily error is not constant, so the only way to determine when a leap second is required is through astronomical observations.
Leap days correct our orbit around the sun to keep December/January in the middle of winter for the Northern Hemisphere.
While true, that is the intent, has any one noticed that this has failed over the last 20 years or so? When I was a child, Winter was Winter, and the first snow fall in the Northeast was usually by Thanksgiving. Over the past couple decades, the first snowfall seems to be pushing itself into late January, mid-February. Used to be, the harshest part of Winter was Dec-Jan, now it seems firmly seated in February. And why is it every year we see an Indian Summer smack in the middle of Winter? By my reckoning, we're now at least a month off (April frost brings May snot).
The Admin and the Engineer
The trouble with that is twofold:
1. Ordinary people who don't take note of such things can have their clocks be off by a second (or even a few) and still get along in their ordinary lives. That would not be the case if the government announced that there was going to be a leap hour inserted this year and they missed it.
2. Any semi-periodic event that must be noted and accommodated by the general public that cannot be calendared years in advance is virtually guaranteed to be a snarling mess.
Who gives a damn about the sun being overhead at 12PM? China operates in a single timezone, despite spanning something like five, and they do just fine.
Give us GMT. Let noon drift where noon drifts. Just keep the seasons in line with the longest and shortest days and forget the rest.
Not surprised, there is really no need to. Your GPSr doesn't care what time it is in human terms, it just needs a number that it can use to caclulate signals relative to each other. That could be anything, possibly even the number of seconds that have passed since 1970.
I would be more surprised if they acutally didupdate GPS satellites with leap second fixes. I would think you would have to recilibrate all the satellites.
*Note* I do office magic, not satellite magic.
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By the way, for extra fun, although all UK systems operate as if legal time is UTC, in fact it's GMT, which is either UT0 or UT1 depending on who you ask. There was legislation being worked on in 1997 to standardise on UTC, but it wasn't restarted after the change of government. So telecoms companies complaining that they don't like leap seconds but `have to' because of legal requirements are simply wrong: they should be ticking UT0 or UT1 for their billing systems, which don't have leap seconds anyway.
ian
Yeah. an hour is meant to be 1/24 of a day. but unfortunatly, every day has a different length. You can have a look at the length of the days for each day the past 2 years here: http://hpiers.obspm.fr/eop-pc/
Yep, that means that meanwhile, our clocks are far more precise than the earth rotation itself.
bickerdyke
Around 43,200 years, actually.
Averages are wonderful things. Over time they account for variations in, well, just about everything. So, yeah, I'll assume that the average rate over millennia is predictable once we've measured it for the few millennia between the needs for a leap hour. A large enough data set and all that.
Doesn't a leap second smack of someone looking overhead at "high noon" each day and re-setting their watch? I mean, really. Next people will want time zones sliced into second increments so that everyone has the sun directly overhead at noon. I wonder if I could patent a watch that uses radio transceiver to re-set itself as you drive from one "time slice" to another as you cross town.
In 2006 there was a pretty bad storm in Buffalo NY in October...
October Storm
Aren't anecdotes wonderful?