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Tuesday, March 7, 2017

If this is 2 p.m. it must be noon

     Confused? Here's how it works. Alaska used to have four time zones: 0ne for Southeastern (Juneau); a large central one (Anchorage, Fairbanks. Barrow); west coast (Bethel, Nome); and one in the western Aleutians.
     Juneau was one time zone removed from Seattle, Anchorage one removed from Juneau, Bethel one removed from Anchorage; and western Aleutians one removed from Bethel.
     Then several years ago the Legislature chose to ignore geography and put everyone on the same time zone. The zone the solons chose was Juneau's which put the whole state except the Aleutians, only one time zone removed from Seattle, and more importantly only four earlier than New York, mostly so stock brokers in Anchorage didn't have to wake up so early to work the markets. Mind you, this was before the Internet. Then in summer there is Daylight Savings Time which adds another hour to the formula.
     So as a result, Local Noon (another name is Solar Noon) in summer is 2 p.m. And in winter Local Noon is 1 p.m., biorhythms be damned.
     Imagine if Gary Cooper had showed up for the gunfight two hours early.
     Why does this matter? Well, nowadays unless you are totally in tune with the Earth's rotation not much, but only a hundred or so years ago it was very important.
     You see, Local Noon is crucial to celestial navigation. It was all the early explorers had. If no one ever explained it to you longitude is measured in degrees, minutes and seconds from the Prime Meridian, and knowing local noon is the key to finding out how far you are from the prime. In order to learn Local Noon, what they did was take sights with a sextant measuring the sun's height above the horizon. From what was believed to be, say, 11:30 a.m. sailors took sights at short, regular intervals. Before noon the angle to the sun would rise slightly with each sight. The minute it showed a drop, they had the best approximation of Local Noon, the highest point reached above the horizon that day. Comparing this with the ship's chronometer set to the time at the prime meridian, they had their longitude. Some mathematical calculations were involved as well. Keep in mind accuracy is necessary, every second the clock is off amounts to a quarter of a mile, so it it is a minute off the ship is 15 miles from where the captain thinks it is. A couple minutes and you could miss Hawaii.
     The problem for the early sailors was no one had a reliable chronometer. They never could be sure of the time at the Prime so to speak. The British Admiralty even offered a large money prize for anyone who could design such a marvel. Seventy years passed before anyone claimed the prize.
     And what does this have to do with Alaska? Well, Captain James Cook was the first to give that chronometer a shot. He explored and charted much of the West Coast and in particular Alaska's coast looking for the fabled northwest passage. He never found it, but his charts were so accurate they are still valid today. So it looks like the thing worked. But imagine if the time had been two hours earlier as it is today. Cook would have been in the Aleutians thinking he was in Prince William Sound. Of course he might have arrived on that beach in Hawaii two hours early and missed the battle that killed him.
     Now wasn't that fun? Just think. You can sleep until noon by the clock, you're really getting up at 10 a.m. not nearly as embarrassing, in Alaska anyway, but the business people get their extra hour of sleep.

A&E network produced a series about the development of the chronometer titled Longitude.

A post script: I have always loved the saying attributed to the ubiquitous Old Indian about Daylight Savings Time: "Only the white man would cut the bottom off a blanket and then sew it to the top and tell you it was a longer blanket."

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