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 ;)

Comments

Re:How did you use yours?

[lousyd]

Do any NTP servers keep track of these seconds?

Yes, that's the point of serving the Network Time Protocol...

Re:Highlights problem with ntp...

[thehickcoder]

Actually, if you where doing high precision scientific applications, it seems this type of behavior would be preferred. Because of the leap second there was not 2 seconds between 11:59:59 and 12:00:01 last night. So, using the NTP behavior if I want a timestamp that was exactly 10000000 seconds ago, I get one that represents 10000000 actually elapsed seconds.

Just because everybody agrees to change their clocks doesn't mean time actually slows down or speeds up.