A Brief History of Time(keeping) - Time Week


Insides of a clock. Photo courtesy of Furya.

Written by: Margaret Jacobi

It’s both priceless and free. We buy it though we can never own it. We can count on it without counting it. It exists and doesn’t exist, here, there, everywhere, but nowhere all at once.

Time is weird.

One of the most domineering constants for humankind, time is a fickle thing we are perpetually aware of, yet it remains essentially non-existent, immaterial.

So how did this come to be? How has something intangible become one of the most integral elements structuring how we are able to conceive our lives? And how has it become so important to a functioning society and economy that we still strive to perfect the calculating of it?

The concept of time is critical for our minds to be able to catalog our existence and how we relate to the world, so much so that conscious calculation of time can be traced back to the Egyptians who created the first measurement of time, the sundial.

Between this invention and the next monumental accomplishment involving time several other devices, such as burning candles, water buckets, and sandglasses, were employed to sort the days. Centuries later, in 1300 AD, weight-driven mechanical clocks were used by monasteries and bell towers to indicate the passing of equal hours.

Three hundred more years passed before Galileo created the first pendulum driven clock, the next big innovation. Upon further development, this discovery became an improvement on traditional methods for time keeping, yet it remained unreliable. One more element still had to be addressed before we could achieve what is now our modern conception of time: respective positions on the earth.

This created a big problem some time later, in the 1800s, when railroads became the preferred method of transportation for trade and travel. A standard time was critical for train schedules to be efficient. Great Britain began implementing time standards prior to the United States, who adopted four standard time zones in 1883.

Then, in 1884, the International Meridian Conference was held in Washington DC in order to determine a way to standardize time more comprehensively. The participants established the Greenwich Meridian to be the prime longitudinal meridian for Greenwich Mean Time (GMT), a world time standard, out of which the 24-hour time zone system grew.

Because the earth is 360 degrees wide and makes a full rotation every 24 hours, every GMT time zone is theoretically 15 degrees in width. However, other factors, such as Daylight Savings time (instituted as a means to utilize daylight most effectively during wartime), advancements in understanding the earth’s rotation, and land distribution among various governments, have resulted in a much less succinct application of time keeping.

Today there are 40 different time zones, the 24 standard zones and 16 irregular ones.

GMT has since been antiquated by Coordinated Universal Time (UTC). Around the 1950s, scientists discovered that the earth’s movements are capricious; it can speed up and slow down unpredictably. To compensate for this, the atomic clock was fabricated. Rather than relying on the earth’s motions to keep time, atomic clocks relate to the sun, employing the resonant frequencies of atoms to keep time while their electronic components are controlled by the frequencies of microwave electromagnetic radiation.

The International Bureau of Weights and Measures (BIPM), based in France, calculates the International Atomic Time (TAI) as a mean time from the collective data sent to them by nearly 200 hundred atomic clocks in 50 different laboratories worldwide. The main difference between TAI and UTC is that the former does not necessarily factor in the irregular rotation of the earth. The two are nearly identical aside from the fact that a leap second is added every so often to UTC to compensate for the earth’s unpredictable motion. When these seconds are added is determined by the International Earth Rotation Service (IERS).

Because of the slight inaccuracies of the atomic clock, researchers continued to explore the science of time keeping and have now found a further improvement to the atomic clock: The optical clock.

“Optical clocks measure frequencies in the optical range (as in, visible light), to mark off individual quadrillionths of a second,” says Mark Brown in a Wired article. “That makes them significantly more precise timekeepers than any current clock. As such, optical clocks can keep time to within one second in 3.7 billion years (about as long as life has been on Earth).”

The only problem with this technology is that it is infinitely more accurate than the cables and satellites that transfer the time information all over the world. However, researchers in Germany accomplished sending an accurate optical clock signal across the country only two weeks ago.

“To pull this off, they used an optical fibre link and installed nine signal amplifiers along the fibre to boost the transmission,” says Brown. “In the experiment they transferred the frequency signal with more than ten times the accuracy than would be required for today’s most precise optical clocks.”

This innovation will probably be the future of time keeping and we will all be synced with it. But, it still is curious, all this energy put forth and all these acronyms created for something completely intangible, yet so intrinsic to human organization. Just make sure you are always the one keeping the time; that time is not keeping you.

Other fun facts about time:

-Russia used to have 11 times zones, but canceled daylight savings time and reduced the number of time zones to nine in 2011.

-Starke County in Indiana is split into two time zones. They’ve had five different time zone changes in the past 30 years.

-Sixteen different time zones meet in Antarctica.

-The communist government in China reduced the number of time zones from five to one for the entire country, which means the sun can rise at 5:30 a.m. on one side of the country and 8:00 a.m. on the other.

For more information, check out the BBC’s website on time here.