Ad-Express and Daily Iowegian, Centerville, IA

Community News Network

September 24, 2013

With Earth spinning more slowly, time isn't flying as fast as before

(Continued)

The moment-to-moment monitoring and management by which electrical engineers maintain the flows of current in power grids, whose interconnected components can span thousands of miles, are possible only because of precisely synchronized clocks and high-speed communication by which even the most distant parts of the grid can keep track of each other's status. And forget about talking and texting on cellphones or Googling on your computer without superlatively timed handoffs of billions of signals between cellphone towers and perfectly timed transmissions of data packets crisscrossing the planet at lightning speed only to miraculously reassemble everywhere into coherent Web pages.

"If we relied on the Earth's length of day, we could not have any of this," says O'Brian, whose group at NIST develops, maintains and improves the supremely regular atomic clocks on which all other timekeeping ultimately is based.

An atomic second is defined, in techspeak, as "the duration of 9,192,631,770 periods of the radiation corresponding to the transition between two hyperfine levels of the ground state of cesium 133 atoms." Translation: The cesium atoms behave like magnificently fast pendulums that never, ever waver the way the Earth's rotation does. It is because of those more than 9 billion oscillations per second that it is possible to synchronize clocks with better than millionths-of-a-second precision.

An Earth second, on the other hand, has been defined since early in the 19th century as 1/86,400th of a 24-hour day (60 seconds times 60 minutes times 24 hours = 86,400). The trouble for modern technologies, O'Brian says, is that the planet's length of day "is wandering unpredictably every day."

What's slowing the Earth down? The moon is the biggest and steadiest drag on the Earth's rotation. Think tides here. As the Earth turns, the moon's gravitation pulls on the Earth's oceans and some of the crust below. As the planet rotates, this tidal interaction with the moon acts like the rubber damper on a carnival wheel that slowly brings the rotating wheel to a halt. This accounts for the bulk of the roughly two-millisecond slowdown of Earth's rotation for each century's worth of this tidal drag.

Text Only
Community News Network
  • Dangerous Darkies Logo.png Redskins not the only nickname to cause a stir

    Daniel Snyder has come under fire for refusing to change the mascot of his NFL team, the Washington Redskins. The Redskins, however, are far from being the only controversial mascot in sports history.  Here is a sampling of athletic teams from all areas of the sports world that were outside the norm.

    July 28, 2014 3 Photos

  • 'Rebel' mascot rising from the dead

    Students and alumni from a Richmond, Va.-area high school are seeking to revive the school's historic mascot, a Confederate soldier known as the "Rebel Man," spurring debate about the appropriateness of public school connections to the Civil War and its icons.

    July 28, 2014

  • Fast food comes to standstill in China

    The shortage of meat is the result of China's latest food scandal, in which a Shanghai supplier allegedly tackled the problem of expired meat by putting it in new packaging and shipping it to fast-food restaurants around the country

    July 28, 2014

  • wd saturday tobias .jpg Stranger’s generosity stuns Ohio veteran

    Vietnam War veteran David A. Tobias was overwhelmed recently when a fellow customer at an OfficeMax store near Ashtabula, Ohio paid for a computer he was purchasing.

    July 28, 2014 1 Photo

  • Screen Shot 2014-07-28 at 1.33.11 PM.png VIDEO: High-dive accident caught on tape

    A woman at a water park in Idaho leaped off a 22-foot high dive platform, then tried to pull herself back up with frightening results. Fortunately, she escaped with only a cut to her finger.

    July 28, 2014 1 Photo

  • CATS-DOGS281.jpg Where cats are more popular than dogs in the U.S.-and all over the world

    We all know there are only two types of people in the world: cat people and dog people. But data from market research firm Euromonitor suggest that these differences extend beyond individual preferences and to the realm of geopolitics: it turns out there are cat countries and dog countries, too.

    July 28, 2014 1 Photo

  • How spy agencies keep their 'toys' from law enforcement

    A little over a decade ago, federal prosecutors used keystroke logging software to steal the encryption password of an alleged New Jersey mobster, Nicodemo Scarfo Jr., so they could get evidence from his computer to be used at his trial.

    July 25, 2014

  • Russia's war on McDonald's takes aim at the Filet-o-Fish

    Russia said earlier this week that it had no intention of answering Western sanctions by making it harder for Western companies to conduct business in Russia.
    But all bets are off, apparently, when you threaten the Russian waistline.

    July 25, 2014

  • cleaning supplies Don't judge mothers with messy homes

    I was building shelves in my garage when a neighbor girl, one of my 4-year-old daughter's friends, approached me and said, "I just saw in your house. It's pretty dirty. Norah's mommy needs to clean more."

    July 25, 2014 1 Photo

  • Arizona's prolonged lethal injection is fourth in U.S. this year

    Arizona's execution of double-murderer Joseph Wood marked the fourth time this year that a state failed to dispatch a convict efficiently, according to the Constitution Project, a bipartisan legal group.3

    July 24, 2014

  • Police Brutality screen shot. Technology plays key part in battling police brutality (VIDEO)

    Allegations of police brutality are nothing new -- as long as there has been law enforcement, citizens have registered claims that some officers cross the line. But in the last few years, the claims of excessive force are being corroborated with new technology from cell phone cameras, police dash-cams and surveillance videos. 

    July 24, 2014 1 Photo

  • Facebook continues moneymaking trend

    Facebook seems to have figured out - for now at least - the holy grail for all media right now: how to make money selling mobile ads.

    July 24, 2014

  • Has the ipad lost its swag?

    July 24, 2014

  • Almost half of America's obese youth don't know they're obese

    The good news is that after decades of furious growth, obesity rates finally seem to be leveling off in the U.S.. The bad news is that America's youth still appear to be dangerously unaware of the problem.

    July 23, 2014

  • Darth Vader is polling higher than all potential 2016 presidential candidates

    On the other hand, with a net favorability of -8, Jar Jar is considerably more popular than the U.S. Congress, which currently enjoys a net favorability rating of -65.

    July 23, 2014

Obituaries
Featured Ads
Poll

The Iowegian wants readers to think about the solicitation ordinance that will prevent groups or individuals from entering a roadway to solicit money. The Centerville City Council in June by a 5-0 vote passed the first reading of just such an ordinance. Public pressure and during a subsequent special meeting, the council voted 3-2 to table the ordinance. A second special meeting to discuss the solicitation ordinance is scheduled for 5:30 p.m. Thursday, Aug. 7 at City Hall. So, the question of the week is, "Do you or do you not support the ordinance to prevent solicitation of funds in city streets?"

A. I support the ordinance
B. I do not support the ordinance
C. Not sure
     View Results
Iowegian on Facebook