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31 December 2011

Ceci n'est pas une horloge / Eloi 0, Morlocks 388 (final) / if you know more than I do about Time, seek professional help promptly / Leap Second tonight? Is the Universe running slow or fast?

Click images, they probably get bigger.
Maybe they will even make more sense.

A Christmukkah/Solstice Gift for the household finally arrived a couple of days after Christmas, and Lo! The fucking thing works like a champ, and now we know EXACTLY what time it is in the upstairs bathroom. (Which is nearly always the exact time in other parts of the house and Earth and the Solar System and, for all I know, the Universe).

(Previously we relied on a $5 piece of crap from Target that reliably told us the Wrong Time. It was of very little comfort to know that it was perfectly correct twice a day.)

One of Vleeptron's first PizzaQ's was about my strange clock, which worked great whenever I took trips into the Far Future (to see the big football match between the Morlocks and the Eloi), but if I took it back to 1880, or the Paleozoic Era, the fucking thing had no clue what time it was, it was useless. 

What kind of verkakte clock works great in the future, but doesn't work at all in the past?

Well of course that's because these thingies aren't clocks at all. They're radios, designed to listen for a special computerized government radio signal, and automatically decode it.

When you install its battery, at first it just sits there confused and clueless, and sulks and won't tell time or do anything. It is doing a perfect impersonation of a broken, useless clock that you will soon have to repackage and send back to the Atomic Clock store, with an annoyed complaint.

But if you just leave it alone overnight (the government signal travels best and strongest at night -- it's an ionosphere thing), eventually it will automatically acquire the WWV radio signal, decode it, and then the hour and minute hands do this crazy whack dance around and around, until finally the hands arrive on the EXACT TIME. And stay there.

It's almost worth standing in front of the clock for hours waiting for the hands to do their whirly whacky dance.

This is my third atomic clock. (They keep getting cheaper and simpler.) I don't know why I love these gizmos -- in elementary and junior high school we had a phrase: "Fun for the feeble-minded."

I think it's because you sort of maybe think you sort of maybe know what time it probably is or might be.

But I REALLY know what time it is. In a million years, I won't be more than one second late for a dentist appointment.

* * *

an e-mail to SW.M.B.O. about the new muy starwarz dingus, the clock which is not a clock. (She loves it.) This is not a clock.

* * *
Them machines on the right count the natural vibrations of [a specific isotope of] the cesium atom, and that keeps time to some astonishing precision, like 1 second every million years. As my audio engineer pals were wont to say: Close enough for rock n roll!
(In my Army helicopter repair factory, everyone would say "Close enough for government work," and toss the piece of precision machinery into a bin.) 

On the left is the format the radio station uses to broadcast the time, date, and a whole bunch of other arcana, like sunspot and radio interference predictions. Mostly the only thing in the signal anybody cares about is the Time and Date (and of course if it's Daylight Savings Time or Whatever). 

UTC refers to

Coordinated Universal Time (UTC) is the primary time standard by which the world regulates clocks and time. It is one of several closely related successors to Greenwich Mean Time. Computer servers, online services and other entities that rely on having a universally accepted time use UTC for that purpose. If only limited precision is needed, clients can obtain the current UTC time from a number of official internet UTC servers. For sub-microsecond precision, clients can obtain the time from satellite signals. Time zones around the world are expressed as positive or negative offsets from UTC, as in this list.
Coordinated Universal Time is based on International Atomic Time (TAI), a time standard calculated using a weighted average of signals from atomic clocks located in nearly 70 national laboratories around the world.[1] The only difference between the two is that UTC is occasionally adjusted by adding a leap second in order to keep it within one second of UT1, which is defined by the Earth's rotation. In the 50 years up to and including 2011, a total of 34 leap seconds have been added.
The UTC standard was officially standardized in 1961 by the International Radio Consultative Committee, after having been initiated by several national time laboratories. The system was changed several times over the following years, until leap seconds were adopted in 1972. A number of proposals have been made to replace it with a new system, which would eliminate leap seconds, but no consensus has yet been reached to do so.

... but its close friends just call it Greenwich Mean Time or Zulu Time. If you know the precise differences between UTC, Greenwich and Zulu, then you know way too much about systems of time measurement.

We're usually UTC - 5 , because UTC originates at the Old Royal Observatory in Greenwich, so they're 5 hours ahead of us. Their motto is "The place where time begins," and they ain't jivin'. (For a brief time the Paris Observatory claimed that time began there, not with those filthy English pig astronomers, but eventually Greenwich won out.)

Schoolchildren and your husband like to skip over an illuminated line in the sidewalk and jump from the Western Hemisphere to the Eastern Hemisphere, and then back again. This is a source of endless mirth, thrill and delight.

I don't know if we're adding a Leap Second tonight. I don't know if the Universe is running fast or slow.

It's an awfully dreamy campus, designed by Christopher Wren, surrounded by a gorgeous big park, and down the hill you can see the Thames and Queens House, which is by Inigo Jones. One night Halley, the Astronomer Royal (and career Naval officer), got drunk with Peter the Great, and they pushed each other all over the place in a wheelbarrow.

Ships in the Thames can look up at the Observatory tower and, EXACTLY at noon, see the metal Time Ball drop, and thus the ship could precisely set its own on-board chronomometer, a setting which would keep the sailors from perishing no matter how far around the world they sail. If you can see the Time Ball drop, you'll always know the exact time, and consequently you can always compute the exact longitude. 
(Before this system, shipwrecks, and weeks lost far from fresh water, were common.)
The wonderful Harrison Chronometers, by which the self-taught clockmaker solved the Longitude problem, are still at the Observatory ticking away like ... well, clockwork. The hearts of the clock mechanism are not metal, but gears of self-lubricating lignum vitae wood.

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