This is an archived article that was published on sltrib.com in 2016, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.
With its months of divisive politics and long list of notable deaths, 2016 is widely derided as one of the planet's worst trips around the sun.
But Earthlings eager for a new beginning in 2017 will have to wait a little longer: one second longer, to be precise.
In addition to February's leap day, which extended the 2016 calendar by 24 hours, a "leap second" is being added to official clocks Saturday to account for inconsistencies in Earth's rotation.
For states on Mountain Standard Time, like Utah, that means the accurate time Saturday afternoon will tick from 4:59:59 p.m. to 4:59:60 p.m. and finally 5:00:00 p.m.
"The Earth's rotation just doesn't want to do what our clocks are saying," said Patrick Wiggins, NASA solar system ambassador to Utah. "We can't adjust the Earth's rotation, so we have to adjust the clocks."
Unlike leap days, which occur on a consistent schedule, leap seconds are applied as needed to adjust for deviations in global rotation and orbit.
The practice began in 1972, according to Vox, with positive leap seconds — or additional time — being applied in 27 out of the past 44 years, including in July 2015. Negative leap seconds — or a subtraction of time — have never been implemented.
Because the leap is for a single second, analog and most personal timepieces don't require adjustment. But some digital systems can be tripped up by the shift in time keeping, like the July 2012 leap second that caused glitches for Reddit, Mozilla, Gawker Media and other websites.
In 2012, Linux creator Linus Torvalds told Wired that each leap second causes an issue in the Linux operating system.
"It's really annoying," he said, "because it's a classic case of code that is basically never run, and thus not tested by users under their normal conditions."
Wiggins said leap seconds are one of many tools that have been used throughout human history to adjust and correct time keeping.
When the Gregorian — or modern — calendar was introduced in 1582 as a replacement to the Julian calendar, Wiggins said, a "leap week" was needed to correct centuries of error.
That meant going to sleep Oct. 4 and waking up Oct. 15, the next day.
Without leap seconds, Wiggins said, similar issues would accumulate over time.
"It would take something like 5,000 years in order for the clocks to be off one hour," he said.
Because the extra second is imperceptible, Wiggins recommends logging onto http://www.time.gov Saturday afternoon to watch the adjustment live.
And because leap seconds occur as needed, Wiggins said, it could be years before the next adjustment, if it ever happens again.
"There's no telling for sure when the next leap second will be added," Wiggins wrote in an email to The Salt Lake Tribune, "so spend this one wisely."
Twitter: @bjaminwood