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125 Years of Longitude 0 0' 00" At Greenwich

Posted by kdawson on from the does-anybody-really-know-what-place-it-is dept.

An anonymous reader writes "This week marks the 125th anniversary of the International Meridian Conference, which determined that the prime meridian (i.e., longitude 0 0' 00") would travel through Greenwich, UK. One of the reasons that Greenwich was agreed upon 'was that 72% of the world's shipping already depended on sea charts that used Greenwich as the Prime Meridian.' Sandford Fleming's proposal of a single 24-hour clock for the entire world, located at the center of the Earth and not linked to any surface meridian, was rejected / not voted on, as it was felt to be outside the purview of the conference."

6 of 429 comments (clear)

  1. 125 MORE years until the US gets time... by Anonymous Coward · · Score: 5, Insightful

    I wonder how much longer it will take for the US to catch up?

    For example, we continue to teach date formatted in a completely nonsense format (MM/DD/YYYY) instead of either high to low (YYYY/MM/DD) or low to high (DD/MM/YYYY) like the rest of the world. Plus using AM/PM instead of 24 hour ("Military Time") again like the rest of the civilised world.

    Don't even get me started on our lack of metric....

    1. Re:125 MORE years until the US gets time... by PhunkySchtuff · · Score: 5, Insightful

      Yet you have a holiday called the Fourth of July...

      --
      Specialist Mac support for creative pros, Melbourne
    2. Re:125 MORE years until the US gets time... by Anonymous Coward · · Score: 5, Insightful

      People in other English speaking countries say it correctly too (e.g. "[the] first of April two thousand and ten"). Americans say it wrong because they write it wrong.

    3. Re:125 MORE years until the US gets time... by Anonymous Coward · · Score: 5, Insightful

      Saying "April 1st" feels more natural to English-speaking people

      Not to *this* English speaker. Some English speakers come from places other than the US.

    4. Re:125 MORE years until the US gets time... by 91degrees · · Score: 5, Insightful

      It was a good decision. There's no YYYY-DD-MM notation so it's not going to get confused with that. It also means a simple alphanumeric sort will sort the date correctly, a decent number of people in the world (Mostly in China and Japan) are already familiar with the notation, and it maintains logical consistency if you put 24 hour time after it (YYYY-MM-DD-hh:mm:ss)

  2. Re:It's because meters and feet are the same by BlueParrot · · Score: 5, Insightful

    Seriously, the metric system has a lot going for it in some ways, but is harder in others. For example, while 10 is a great multiplier (since we tend to think in base 10), it doesn't have a lot of factors.

    You miss the point. The advantage of using the same base across all measurements is not merely that it goes well with the digits we use, but it means different type of measurements work well together. A cubic meter works out to exactly a thousand liters, which when filled with water would weigh 1 metric tonne, which is 1 thousand kilograms. The pressure of 10 metres of water works out to 1 atmosphere, which is approximately 100,000 Pascal, which is 100,000 Newtons per square meter. At sea level the acceleration due to gravity is approximately 10 M/s so 1kg is roughly 10 newtons worth of weight. If you have a force of 1 Newton over 1 meter , you get 1 joule worth of energy, which is the energy drawn per second by 1 ampere of electric current at an electric potential of 1 volt.

    Now, lets say you have a pool of water that is 10 feet deep and 10x20 yards by the sides. You want an electric engine operating at 230V to drive a pump that can empty the pool through a pipe that has a diameter of 3inches. The drain is at ground level. You don't want to leave it on unsupervised at night so you want it to take no more than 2 hours. How many amperes of current will your engine draw? What's the total amount of energy necessary to empty the pool? How much pressure does the pump have to handle?

    I would STRONGLY suggest you convert to SI units before trying to solve that problem.