It’s Official: The Leap Second Survives

  • Share
  • Read Later
Getty Images

Fans of the leap second, you can breathe easy. Your favorite little tick of the clock is safe — for now.

The leap second, for those less chronometrically oriented, is the additional second the U.N.’s International Telecommunication Union (ITU) adds to the world’s atomic clocks every few years to make up for the fact that the earth’s rotation is not a completely consistent thing. Yes, it takes the planet 24 hours — give or take — to make a single turn, but a whole variety of factors, from tides to earthquakes to the gravitational tug of the sun and moon, can slow that down a bit. According to the International Earth Rotation & Reference Systems Service (yes, such a group exists), the planet taps the brakes by about one-fifteenth of a second per year. So for the past 40 years, the ITU has been making the occasional adjustment to keep everything in line.

(PHOTOS: Seeking Art in Science)

Tidiness alone suggests that this painless exercise is worth continuing, since it’s the rotation of the earth, after all, that led us to adopt a 24-hour clock in the first place. Abandoning the rotation standard would be the astronomical equivalent of going off the gold standard — except without Ron Paul to complain about it. But tidiness isn’t all that’s at stake.

Every time a leap second gets added, supercomputers, space telescopes, and weapons, navigation and communications systems have to be adjusted. If one such network doesn’t get the ITU memo, the results, in theory, could be disastrous. Better, then, to tolerate the planet’s occasionally dilatory spin than to risk blowing the thing up with some technological “oops” like an unintended missile strike.

For that reason, at today’s meeting of the ITU, in Geneva, a group of countries led by the U.S., Japan, Canada, Italy, Mexico and France argued for scrapping the leap second once and for all. Another group, led by the U.K. and Germany, argued for it to stay. But as with so many international gatherings, it was a third group — the let’s-think-about-it-and-discuss-it-again-in-a-few-years caucus — that prevailed. In this case, that bloc included Russia, Turkey and Nigeria, which successfully had the motion tabled until 2015.

Ultimately, safety will probably trump tradition, which means that leap-second lovers should brace themselves for some bad news down the line. The odds are that the major news networks won’t be running a countdown clock leading up to the big decision in 2015 — but if they did, they could probably quit worrying about having to adjust it every few years.

PHOTOS: Very Small Things