20 Things You Didn't Know About... Time

20 Things You Didn't Know About... Time
The beginning, the end, and the funny habits of our favorite ticking force.

by LeeAundra Temescu
From the March 2009 issue, published online March 12, 2009

Yahoo! BuzzShareThisShareThis

iStockphoto
1 “Time is an illusion. Lunchtime doubly so,” joked Douglas Adams in The Hitchhiker’s Guide to the Galaxy. Scientists aren’t laughing, though. Some speculative new physics theories suggest that time emerges from a more fundamental—and timeless—reality.

2 Try explaining that when you get to work late. The average U.S. city commuter loses 38 hours a year to traffic delays.

3 Wonder why you have to set your clock ahead in March? Daylight Saving Time began as a joke by Benjamin Franklin, who proposed waking people earlier on bright summer mornings so they might work more during the day and thus save candles. It was introduced in the U.K. in 1917 and then spread around the world.


--------------------------------------------------------------------------------

advertisement | article continues below


--------------------------------------------------------------------------------


4 Green days. The Department of Energy estimates that electricity demand drops by 0.5 percent during Daylight Saving Time, saving the equivalent of nearly 3 million barrels of oil.

5 By observing how quickly bank tellers made change, pedestrians walked, and postal clerks spoke, psychologists determined that the three fastest-paced U.S. cities are Boston, Buffalo, and New York.

6 The three slowest? Shreveport, Sacramento, and L.A.

7 One second used to be defined as 1/86,400 the length of a day. However, Earth’s rotation isn’t perfectly reliable. Tidal friction from the sun and moon slows our planet and increases the length of a day by 3 milli­seconds per century.

8 This means that in the time of the dinosaurs, the day was just 23 hours long.

9 Weather also changes the day. During El Niño events, strong winds can slow Earth’s rotation by a fraction of a milli­second every 24 hours.

10 Modern technology can do better. In 1972 a network of atomic clocks in more than 50 countries was made the final authority on time, so accurate that it takes 31.7 million years to lose about one second.

11 To keep this time in sync with Earth’s slowing rotation, a “leap second” must be added every few years, most recently this past New Year’s Eve.

12 The world’s most accurate clock, at the National Institute of Standards and Technology in Colorado, measures vibrations of a single atom of mercury. In a billion years it will not lose one second.

13 Until the 1800s, every village lived in its own little time zone, with clocks synchronized to the local solar noon.

14 This caused havoc with the advent of trains and timetables. For a while watches were made that could tell both local time and “railway time.”

15 On November 18, 1883, American railway companies forced the national adoption of standardized time zones.

16 Thinking about how railway time required clocks in different places to be synchronized may have inspired Einstein to develop his theory of relativity, which unifies space and time.

17 Einstein showed that gravity makes time run more slowly. Thus airplane passengers, flying where Earth’s pull is weaker, age a few extra nano­seconds each flight.

18 According to quantum theory, the shortest moment of time that can exist is known as Planck time, or 0.0000000000000000000000000000000000000000001 second.

19 Time has not been around forever. Most scientists believe it was created along with the rest of the universe in the Big Bang, 13.7 billion years ago.

20 There may be an end of time. Three Spanish scientists posit that the observed acceleration of the expanding cosmos is an illusion caused by the slowing of time. According to their math, time may eventually stop, at which point everything will come to a standstill.

Related Articles
20 Things You Didn't Know About... Sugar
We eat it, we love it, and it may have been a chemical precursor to life on Earth. October 30, 2009

20 Things You Didn't Know About... Hurricanes
A typical hurricane releases some 600 trillion watts of heat energy, equivalent to 200 times the world’s total electrical generating capacity. August 18, 2009

20 Things You Didn't Know About... Eclipses
July 30, 2009

20 Things You Didn't Know About... Movies
The first skin flicks, setting actors on fire (safely), the great bluff that turned into IMAX, and more. June 03, 2009

20 Things You Didn't Know About... Tunnels
New York has a forgotten one, Texas has a $2 billion wasted one, and Switzerland's building the longest. April 29, 2009
Latest News Blogs Most Popular
The Bizarre and Brilliant World of Knitted Science
How Autistic Artists See the World
Eye Color Explained
Each Grain of Sand a Tiny Work of Art
The Brain: What Is the Speed of Thought?
#91: The Strange Ancient Process That Made Earth's Oxygen
#93: Re-Analyzing One of the Greatest Brains in History
The Brain: Humanity's Other Basic Instinct: Math
#92: Nowhere to Hide From the Buzz of Civilization
#95: Hidden Caribou-Hunting Civilization Found Under Lake Huron
Video for Owning the Weather Panel in Copenhagen
Easy-reading chiropractic libel for young readers
Create your own tour of the Universe!
Geek culture
Republicans Thrash Climate Scientists in the Court of Public Opinion
Terroreidolia
New Especially Bad Heroin Can Give You an Overdose—or Anthrax
From Tibet to Infinity and back again
Ocean Volcano Eruption!!
Furious Fanboys Plan “Operation Stranglehold” to Take Down AT&T
Lab-Created Platelets Slow Bleeding in Rodents
Physicists Find Hints of Dark Matter But No Clear Discovery
The Mutations That Kill: 1st Cancer Genomes Sequenced
Copenhagen Roundup: Protests, Walkouts, and the Money Wars
A Hack of the Drones: Insurgents Spy on Spy Planes With $26 Software
Study: Like Earthquakes & Financial Markets, Terrorist Attacks Follow Laws ...
New Super-Earth: Hot, Watery, and Nearby
Injured Vet Receives Transplanted Pancreas Grown From a Few Cells
Scientist Smackdown: Are Unnecessary CT Scans Killing People?
Gravity Satellites Show a Huge Groundwater Loss in California



Name

Address

Address

City State Zip Code

Email Address


(U.S. orders only) DISCOVER is published monthly except two double issues which count as two each. Savings based on a $29.95 annual subscription rate.