As you may know, if you have peeked at next month’s calendar page, 2012 is a leap year. The major beef I have with leap year is: why do we have to add the extra day in February, the most appalling month weather-wise? Why can’t we add it in June or during summer vacation? Wouldn’t an extra day of really nice weather be so much better?
As it happens, and to add insult to injury, we
are getting some extra time in June: one second. That is, a “leap second” that periodically needs to be inserted into the calendar to keep the imprecise timekeeping of the Earth synchronized with the anal retentively precise timekeeping of scientists. The length of time that it takes the Earth to go around the Sun is not a precise 365 days, but in actuality 365.242 days. Hence we need to add some time every now and then. Then there is the problem that the Earth is slowing and, as a result, days are getting longer. (In 1820, one day comprised 86,400 seconds, but now there are about 86,400.002 seconds.) Phil Plait over at the
Bad Astronomy blog, explains in detail the “leaping” business, and points out: “The day has
2 extra milliseconds in it. That may not sound like much, but it adds up. Over the course of a single year we have an extra 365 of those 2 millisecond slices of time. That adds up to about 0.73 seconds every year. After a year, the calendar is off by about 3/4 of a second because the Earth’s rotation is slow. In two years that’s 1.46 seconds, and after ten years it’s over 7 seconds!”
Needless to say, not everyone thinks that it’s vitally important to keep the two clocks—ours and the Earth’s—in sync. And there is a bit of a Monk-like aspect to it, I will admit. (Also, too, I am told that leap seconds
do cause some troubles for navigation, telecommunication, and computer systems.) Scientists, too, are split on whether to keep them up or to just “cut the cord.” And other computer systems were developed taking leap seconds into account—and “going off the leap second” may cause problems for
them.
Last October, the Colloquium on Decoupling Civil Timekeeping from Earth Rotation was held and generated—as you can well imagine—a highly compelling
paper. I’ll read it at some point—I just haven’t the time.