6 ms·

Oh, so I can annoy my friends by counting down to the new year "correctly", one second after them.

by TorKlingberg 10y ago

tonmoy 10y ago
Only if you are in UTC timezone I suppose
- tspiteri 10y ago
  It is unclear for timezones behind UTC. If you are in UTC+1, the leap second happens at 1 am, so the countdown would be over: no fun here. If on the other hand you are in UTC-1, the leap second happens at 11 pm, so if the countdown clocks are not corrected for the leap second, friends can still be annoyed.
  - suanmeiguo 10y ago
    Either way, your friends will be annoyed..
  - Dylan16807 10y ago
    What clock is set that precisely, hasn't drifted since being set, and won't pick up the correction by itself?
    - tspiteri 10y ago
      A GPS watch without a firmware update to handle the latest leap second?
      - Dylan16807 10y ago
        GPS announces leap seconds well in advance.
joeax 10y ago
Your phone should update at one second before midnight UTC. So if your in EST then at 6:59:59, watch for 59 to be counted twice.
- andrewstuart2 10y ago
  Have our timekeeping protocols really accounted for future events like that? It's my understanding that NTP really only synchronizes time periodically.
  - lmm 10y ago
    Your phone/computer should (according to the standard) know when the leap second is and apply it. NTP etc. transmit the information about leap seconds well in advance.
  - detaro 10y ago
    NTP includes flags for "leap second at the end of day", so devices that check NTP time at least once a day get the information. The systems internal list of leap seconds is possibly updated before that through normal system updates.
  - kqr 10y ago
    It is possible your device may not see a leap second, only eventually observe that it is running one second slow, and smear to correct for that.
- gshubert17 10y ago
  I believe 6:59:59 will be followed by 6:59:60. See the screen shot I took of a leap second added in 2008. https://www.flickr.com/photos/127045916@N06/31678955582/ https://www.flickr.com/photos/127045916@N06/31678955582/
  - devy 10y ago
    Yep. The extra second is the 60th second. http://earthsky.org/human-world/leap-second-june-30-december-31-why-need-controversy http://earthsky.org/human-world/leap-second-june-30-december...
pi-squared 10y ago
Depends on where you are: https://time.is/leapsecond https://time.is/leapsecond

Oh, so I can annoy my friends by counting down to the new year "correctly", one second after them.

tonmoy 10y ago

Only if you are in UTC timezone I suppose

tspiteri 10y ago
It is unclear for timezones behind UTC. If you are in UTC+1, the leap second happens at 1 am, so the countdown would be over: no fun here. If on the other hand you are in UTC-1, the leap second happens at 11 pm, so if the countdown clocks are not corrected for the leap second, friends can still be annoyed.
- suanmeiguo 10y ago
  Either way, your friends will be annoyed..
- Dylan16807 10y ago
  What clock is set that precisely, hasn't drifted since being set, and won't pick up the correction by itself?
  - tspiteri 10y ago
    A GPS watch without a firmware update to handle the latest leap second?
    - Dylan16807 10y ago
      GPS announces leap seconds well in advance.

joeax 10y ago

Your phone should update at one second before midnight UTC. So if your in EST then at 6:59:59, watch for 59 to be counted twice.

andrewstuart2 10y ago
Have our timekeeping protocols really accounted for future events like that? It's my understanding that NTP really only synchronizes time periodically.
- lmm 10y ago
  Your phone/computer should (according to the standard) know when the leap second is and apply it. NTP etc. transmit the information about leap seconds well in advance.
- detaro 10y ago
  NTP includes flags for "leap second at the end of day", so devices that check NTP time at least once a day get the information. The systems internal list of leap seconds is possibly updated before that through normal system updates.
- kqr 10y ago
  It is possible your device may not see a leap second, only eventually observe that it is running one second slow, and smear to correct for that.
gshubert17 10y ago
I believe 6:59:59 will be followed by 6:59:60. See the screen shot I took of a leap second added in 2008. https://www.flickr.com/photos/127045916@N06/31678955582/ https://www.flickr.com/photos/127045916@N06/31678955582/
- devy 10y ago
  Yep. The extra second is the 60th second. http://earthsky.org/human-world/leap-second-june-30-december-31-why-need-controversy http://earthsky.org/human-world/leap-second-june-30-december...

pi-squared 10y ago

Depends on where you are: https://time.is/leapsecond https://time.is/leapsecond