According to Ford Prefect in the Hitchhiker’s Guide to the Galaxy, “All time is relative. Lunch doubly so.” That principle is being proven today, as the day is extend to 24 hours and 1 second.
We measure time in two ways: solar time relative to the earth’s rotation and atomic time based on measurements of the internal oscillations in atoms. But these two relative times will — over the years — go out of synch as solar time varies due to the slowing of the Earth’s rotation because of weather, earthquakes and a butterfly’s wings fluttering. Leap seconds were introduced in the early 1970s to occasionally correct for those variations between solar and atomic time.Today at 23:59:59 (UTC), 4:59:59 p.m. PDT or 7:59:59 p.m. EDT we will get an extra second. Like a leap day, this is an internationally agreed-upon event that happens either December 31st or June 30th. Unlike a leap day, leap seconds do not happen at regular intervals. In fact, the interval between them has varied from 0 to 6 years in their 40-year history.
Because of this inconsistency, the leap second is not without some controversy. In 2005, there was an attempt to phase out the leap second in favor of less regular leap hours. However, for now that proposal has been tabled.
So what will you do with a whole extra second today? Eat an extra potato chip? Read half a haiku? Give your partner a quick peck on the cheek? There is no time to lose! Let us know in the comments.