© J. Kelly BeattyDaylight-saving time is an annoyance for backyard astronomers.
In the wee hours of March 10th, we in the U.S. dutifully reset our clocks forward by an hour, signaling the switch to daylight saving time. Oh, joy! Now I can look forward to having the midsummer Sun set after 8 p.m., and it won't get fully dark for at least another hour after that.
I don't know about you, but our annual switch to daylight time (called "summer time" most everywhere outside the U.S.) does amateur astronomy no favors. Most nights, by the time Sagittarius is up high enough to be seen well, I'm ready to put my head down for sleep.
Things were bad enough - "springing ahead" in April and "falling back" in October - but a few years ago Congress meddled further with Mother Nature when it passed the Energy Policy Act of 2005 and decreed that daylight-saving time would be extended, beginning in 2007.
Now we make the switch from the second Sunday of March until the first Sunday in November, which is about two-thirds of the year. Canada followed our lead, but European countries wait another three weeks to make the switch and Mexico another four.
In fact, although about 75 countries observe some form of summer time, it's mostly a high-latitude phenomenon. Most of the world's population (150+ countries) avoids it altogether, and of course when northern countries are using it, our friends Down Under are not.
So how did all this come about in the first place?