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Leap Second At The End of 2005
Ruff_ilb writes "Because of the discrepency between an ephemeris second (the fraction 1/31,556,925.9747 of the tropical year for 1900 January 0 at 12 hours ephemeris time) and the second of atomic time (the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom), we're left with more than leap years. In order to ensure that the the atomic time and civil stay coordinated, "Civil time is occasionally adjusted by one second increments to ensure that the difference between a uniform time scale defined by atomic clocks does not differ from the Earth's rotational time by more than 0.9 seconds."" And Happy New Years everyone ;)
Most NTP servers use UTC time, so yes.
t - leap second bulletin
http://hpiers.obspm.fr/iers/bul/bulc/bulletinc.da
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So, as of today, any time stamp you have made using NTP, ever, has been retroactively displaced by one second. Intervals that included midnight (UTC) last night are all too short by one second.
This may not be a problem for handling your calendar appointments, but it can muck up all kinds of scientific applications that require high precision.
I watched the time at Time.gov: 23:59:56 (UTC) =>23:59:57=>23:59:58=>23:59:59=>23:59:60!=>00:00:0 0
It was Amazing! This was the first time for me... *remebers where I was at that moment
"The test of the morality of a society is what it does for it's children." -Dietrich Bonhoeffer
"Happy New Year's" is short for "Happy New Year's Day".
The most rabid believers in American Exceptionalism are the exact same people whose policies are destroying it.
Original poster is slightly wrong - it's not the length of the 1900 ephemeris second,
it's the fact that the Earth, like all of us, is getting older and slowing down, so that
the 2005 "Earth rotation" second (i.e. 1/86400 of one spin of the Earth) is longer than
the 1900 equivalent and longer than the atomic time (SI) second. Instead of changing
the length of the second, it is currently deemed less painful to keep using the old
length and stick in an extra second every now and again.
Since this depends on the slop of the Earth's interior, it's not a fully regular and predictable thing - we might even have to remove a second one year.
GPS time just counts intervals, and it started the count in weeks, days, seconds in January, 1980. The system is aware if UTC though, and one of the various messages sent from the satellites includes the UTC offset. So if you receive and decode that message you'd know the UTC time.
As of yesterday, the difference between UTC and GPS time is 14 seconds.
http://maia.usno.navy.mil/ser7/series14.txt
Last year during the Superbowl it was noticeable at my house, I had 3 TVs tuned to the game, 2 via DirecTV and another using rabbit ears, the over the air broadcast was easily 2-3 seconds ahead of the DTV broadcast. This is one of the reasons that the Sport Betting Houses that allow betting up until play completion don't allow cellphones, because you could have someone watching via a faster source or at the game itself, feeding you what's going to happen.
(By "solar" I don't just mean sundials. I mean clocks that are set by pointing the hour hand straight up at noon, which is how all clocks were set before time zones were invented.)
I think what you were trying to say is, "most NTP servers are corrected against official UTC time signals."