Leap seconds

In about ten minutes, just before midnight UTC, a leap second will occur. This day will last slightly longer that most.

What is a leap second?

Similar to a leap day, a leap second is an extra second added to the end of the day. Also like a leap day, the leap second serves to keep our measurement of time in sync with the Earth’s rotation. Unlike leap days, the occurrence of a leap second is variable and are announced only six months in advance because of the Earth’s irregular rotation.

UT1-UTC  difference chart

The difference between UT1 and UTC over time. Courtesy of Wikipedia

What will happen when the leap second occurs?

What you will see depends on how your timepiece handles leap seconds. Those that have proper display support for leap seconds should display 23:59:60 UTC. Those that support leap seconds but cannot display them may show 23:59:59 during the leap second. Devices that do not support leap seconds will continue to 0:00:00 and will have to be manually adjusted.

Should I be concerned?

No, not really. The passing of the leap second is no different from any other second and time does not stop for the duration of the leap second. The only reasonable concern is adjusting all your devices that do not support leap seconds.


Advertisements
2 comments

`$name' says...

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: