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Transportation Earth News

125 Years of Longitude 0 0' 00" At Greenwich 429

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."
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125 Years of Longitude 0 0' 00" At Greenwich

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  • by ls671 ( 1122017 ) * on Wednesday October 21, 2009 @04:06AM (#29820733) Homepage

    And don't forget the 180th meridian that came with it. When you cross the 180th meridian, you have to set your watch back/forward 23 hours !

    Quite a few people are unaware of it ;-))

    http://adsabs.harvard.edu/full/1919PA.....27..416F [harvard.edu]

    • Re: (Score:3, Insightful)

      by FunPika ( 1551249 )
      People still use watches!? Everyone I know just whips out their cell phone when they need to find out what time it is these days.
      • by Pieroxy ( 222434 ) on Wednesday October 21, 2009 @05:54AM (#29821255) Homepage

        I recently flew from LA to Fiji. On the way forward, you land two days after departure, on the way back, you land at the same time you departed...

        It's pretty disturbing.

        • by riflemann ( 190895 ) <riflemann@Nospam.bb.cactii.net> on Wednesday October 21, 2009 @06:50AM (#29821623)

          Flying Sydney, Australia to California is similar. There have been numerous times when I departed Sydney after lunch on Saturday, spend 14 hours in a plane, then land at San Francisco in time for breakfast on _the same day_.

          Amusing chat over IM with a friend one such day:

          Them: How's your Saturday?
          Me: Good, had lunch in Sydney then breakfast in San Francisco after that.
          Them: wtf???

          • by amstrad ( 60839 ) on Wednesday October 21, 2009 @07:49AM (#29822095)
            reminds me of the amusing line from the time travel film Primer [wikipedia.org]

            Aaron: Man, I'm starving. I haven't eaten since later this afternoon.

            • Re: (Score:3, Interesting)

              by TobyRush ( 957946 )

              Primer is a great film, one of my favorites. Just be prepared to invest quite a bit of time into understanding it.

              The discussion reminds me of a story my father tells: for a high school English paper, he was supposed to write about an invention he'd like to create. He decided to create a time machine by placing a centrifuge on one of the earth's poles. He of course left out any mention of the IDL.

              The teacher gave him a perfect score simply because she couldn't figure out why it wouldn't work.

            • Re: (Score:3, Insightful)

              by niktemadur ( 793971 )

              Oh man, I intend this as a high compliment - fifty years from now, Primer is going to be regarded by intellectual snobs (the trendsetters) in Brazil, China, India and Indonesia as maybe the finest example of American Geek Cinema of early Twentieth First Century, so far ahead of its' cultural time that it's almost awe-inspiring.

      • Re: (Score:3, Insightful)

        by Nerdfest ( 867930 )
        Watches seem to be becoming popular again, even if only as a fashion accessory, especially for men. Next time you're watching TV, keep an eye out for large, flashy watches; they're very common.
    • Re: (Score:3, Interesting)

      by niktemadur ( 793971 )

      Reminds me of that limerick:

      A young rocket scientist named Wright
      once traveled much faster than light
      He set out one day, in a relative way
      and arrived on the previous night

      Instead of going through the hassle of upgrading an Orion Project [wikipedia.org] spaceship, all one has to do is fly conventionally from Honolulu to Tokyo.
      Now they tell me!

      • by ls671 ( 1122017 ) *

        Hehe... got you ! ;-)

        I said most people were not used to this...

        It is actually the other way around, you have to fly from Tokyo to Honolulu to land on the previous day ;-)

        Your comment was nevertheless very interesting ;-)

        Cheers,

        • Re: (Score:3, Interesting)

          by niktemadur ( 793971 )

          Hey, thanks for the nod and the insight, I quote the Wikipedia article on the International Date Line:
          "Crossing the IDL travelling east results in a day or approximately 24 hours being subtracted".

          Here's the thing, living on the Pacific Coast of the Americas (Mexico, to be precise), Japan would be to my west, even as a European-style education has drilled into my mind that Japan is to the east. Fun to have a previously shut window of perspective opened ajar, in a gentle manner. Well done, sir!

    • Re: (Score:3, Informative)

      by TBoon ( 1381891 )
      Actually, you'd have to set it 24 hours when crossing the 180th. The (theoretical) timezone-limits for +12 and -12 are only 7.5 degrees each, compared to 15 degrees for the all others. Of course in real life, it only crosses land i Russia and Fiji, and they bend the dateline around themselves to avoid this, so this should only happen at sea.
      • Re: (Score:2, Interesting)

        by Anonymous Coward

        No, timezones are one hour apart and the international date line is the edge between two timezones, so while you cross the date line, you also cross into another timezone: 1d+-1h. This also means that the international date line is not even theoretically the 180th meridian, just like the 0 meridian is the center, not the edge of a time zone.

        • by ls671 ( 1122017 ) *

          Yep, you are right, of course no two adjacent timezone have the same time ! Even if it"s not the same day on each side !

          By the way, you can cross the 180th meridian (officially dateline with exceptions mentioned by another poster) without changing date :

          Coming from Tokyo, you cross the line at 23:30 on say, October 21th, once the line crossed, you are now at 0:30, October 21th ;-))

        • Re: (Score:3, Interesting)

          by 3247 ( 161794 )

          No, timezones are one hour apart and the international date line is the edge between two timezones,...

          Dead wrong.

          Just look at, no read Wikipedia [wikipedia.org]: Most of the IDL is actually in international waters at the 180th meridian and separates the +12:00 time zone from the -12:00 time zone. The difference is 24:00, which is the usual time span of one calendar day.

          However, inhabitated land masses and islands tend to have deviations in their time zones, yielding differences between 21 hours (between Russia and Alaska) and 25 hours (between Tonga and International Waters around it).

          • by ls671 ( 1122017 ) *

            You are technically correct !

            But in truth, the +12/-12 timezone is the same timezone with the dateline in the middle.

            This image makes things a lot clearer:

            http://www.worldtimezone.com/ [worldtimezone.com]

            Since GMT is 0 if we had +12 timezones and -12 timezones we would end up with 25 timezones ;-))

            So +12 and -12 take the same space as as one unique regular timezone would take.

  • by TheReal_sabret00the ( 1604049 ) on Wednesday October 21, 2009 @04:09AM (#29820747) Homepage
    It's a wonderful thing to live a phlegms breath away from such a staple part of our species everyday lives.
  • by Anonymous Coward on Wednesday October 21, 2009 @04:12AM (#29820755)

    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....

    • We're currently 5-10 hours behind, not too far, but we don't seem to be gaining.

    • Re: (Score:3, Funny)

      by Thanshin ( 1188877 )

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

      But you have a beautiful metric, in bodyparts!

      It's perfect for D&D. "I advance five feet" is much more immersive than "I advance two meters".

      Pity that you didn't make a corresponding time system replacing seconds, hours and days by heartbeats, digestions and bodyrottings.

      • by mikael_j ( 106439 ) on Wednesday October 21, 2009 @04:26AM (#29820815)

        Most likely you only think "feet" are better than "meters" in D&D because you're used to imperial units and they feel more "natural" to you. As someone who grew up in a country where inches and feet are units only used when dealing with things imported directly from the US I always have to stop and think for a second when trying to remember how long "five feet" is, or how heavy something that is "150 pounds" really is, and don't get me started on the British use of "stones" for weight...

        /Mikael

        • by Thanshin ( 1188877 ) on Wednesday October 21, 2009 @05:08AM (#29821029)

          I always have to stop and think for a second when trying to remember how long "five feet" is,

          What's to remember? Five feet is the reach of your longsword.

          And I don't care where you live, you should always carry a longsword.

          And 30 feet of rope.

      • Re: (Score:2, Insightful)

        by Hognoxious ( 631665 )

        It's perfect for D&D. "I advance five feet" is much more immersive than "I advance two meters".

        Is that dwarf feet, orc feet or hobbit feet?

    • by putaro ( 235078 ) on Wednesday October 21, 2009 @04:21AM (#29820789) Journal

      While MM/DD/YYYY seems illogical, it maps exactly to the way you say it - April 1st, 2010 = 04/01/2010

      • by dunkelfalke ( 91624 ) on Wednesday October 21, 2009 @04:24AM (#29820799)

        And if I say "1st of April, 2010"?

        • Re: (Score:3, Informative)

          For God's sake, say it any way you want, and write it in ISO YYYY-MM-DD format. Since no-one in the world uses YYYY-DD-MM, it is perfectly unambiguous.

          Personally, I'm constantly irked by the fact that, in Canada, when you see something like 05/10/2010, you never know whether it's month or day first. In general, I see DD/MM more often, but because of strong American influence, every now and then you get a form with MM/DD, so you always have to look out for that.

      • "nth of month, year" isn't exactly uncommon either.

        Also, the written form Americans use causes a lot of confusion when dealing with non-Americans who use yyyy-mm-dd, dd/mm/yyyy or yyyy/mm/dd.

        And as always, I think grandpa Simpson's classic comment really sums up the attitude behind why so many Americans are reluctant to switching; “My car gets forty rods to the hogshead, and that's the way I likes it!”

        /Mikael

        • And as always, I think grandpa Simpson's classic comment really sums up the attitude behind why so many Americans are reluctant to switching; “My car gets forty rods to the hogshead, and that's the way I likes it!”

          /Mikael

          Homer himself would say: Greenwich... mmmm.. pizza!

        • by Mashiki ( 184564 )

          I believe the way they put it when we write our notes for logs is: Use a system for dates. It doesn't matter if it's not the standard in north america. But use a system that works for you. Sometimes retraining someone to a new one simply screws them up.

          Mine is yyyy/mo/dd, my friends is yyyy/dd/mo, one of the inspectors(OPP) that I was taught by uses dd/mo/yyyy. All three are valid.

        • by ae1294 ( 1547521 ) on Wednesday October 21, 2009 @08:38AM (#29822607) Journal

          Also, the written form Americans use causes a lot of confusion when dealing with non-Americans who use yyyy-mm-dd, dd/mm/yyyy or yyyy/mm/dd.

          Why the hell do you think we do it?

          You know we work REALLY REALLY hard to piss you guys off.. I mean we even elected a NICE president this time around just so we could fuck with you and elect Hitler next time... And yes I do mean "The Hitler". He flew out on that last plane that took off from the street right outside the bunker right before the Ruskies took it. We picked him up a few days later trying to enter Sweden. Apparently he had a bunch of gold in some bank there or something, who knows... Anyway we've had to replace most of his body over the years with alien implants we got from the Roswell crash but still you guys are just going to FREAK!

          Hummmm, I wonder what you will think when we start a third war on terror, involving our own terror campaign... We like to call it... Where on earth did those Yankees hide that Hydrogen Bomb!

      • by ionix5891 ( 1228718 ) on Wednesday October 21, 2009 @04:34AM (#29820837)

        While MM/DD/YYYY seems illogical, it maps exactly to the way you say it - April 1st, 2010 = 04/01/2010

        uhm alot of people think in languages other than US English

        • Re: (Score:3, Interesting)

          by razvan784 ( 1389375 )
          ISO 8601 [wikipedia.org] doesn't favor the US or the other notation.
          • by 91degrees ( 207121 ) on Wednesday October 21, 2009 @05:15AM (#29821061) Journal
            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)
        • by Anonymous Coward on Wednesday October 21, 2009 @04:51AM (#29820937)

          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.

      • by PhunkySchtuff ( 208108 ) <kai&automatica,com,au> on Wednesday October 21, 2009 @04:46AM (#29820903) Homepage

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

    • Re: (Score:3, Funny)

      by dword ( 735428 )

      Do you have any idea what that would do to the March Pi Day [wikipedia.org]?

    • by niktemadur ( 793971 ) on Wednesday October 21, 2009 @07:06AM (#29821739)

      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.

      While the AC got modded "Troll", he/she has got a point, expressed in narrow terms, which I'd like to expand at the risk of being Offtopic: Why is it so difficult to standardize things from place to place?

      - Video. The PAL standard is better quality than NTSC (Never The Same Color), so why did the Americas adopt an inferior option?
      - Voltages. Being asthmatic, my wife took her nebulizer on a recent trip to Europe and within ten seconds busted our converter. We busted another one before ordering a special-delivery converter for medium-sized devices, the whole escapade setting us back about 180 CHF.
      - Car filters. Working at a company that distributes car stuff, a trip to the warehouse is an eye opener, there's over 1,500 types of just oil filters, the difference between some of them being half a millimeter in circumference. Add windshield wipers (also windshields, for that matter), engine bands, tires (or tyres for all you Britons, cheers mate), fuses, and I wonder why no institution has put an end to this nonsense, like the API (American Petroleum Institute) did with engine oils (BTW, a shining example of standardization success).
      - Keyboards. Even in Western nations, configurations change however slightly, so that a QWERTY in the USA is a QWERTZ in Switzerland, then another thing in Spain, etc, which tends to REALLY slow down typing speed.
      - DVDs. Take away the PAL and NTSC thing, and you've still got to deal with the DVD+R, DVD-R, DVD+RW, DVD-RW, DVD-DL+R, DVD-DL-R, DVD-DD+R, DVD-DL-R, the majority not compatible with all burners, drives and/or players.
      - Steering wheel/Street flow. Some do it on the left side, some do it on the right side. WHY???

      Best comic strip I've read in the last few months is from Spain, shows some exhausted dude being compared to Sisyphus [wikipedia.org]:
      - "Seven years of toil, but I've finally ripped, subtitled and uploaded all the world's DVDs to the Internet, with cover jpgs and all".
      Then the guy points a gun to his head as an off-voice says:
      - "Now stick them all up your ass, 'cause here comes High Definition, Blu-Ray, HDD and whatever the fuck else".

      End of rant.

      Back on topic, whoever ruled the Seven Seas first, got to do the homework and implement a practical system of navigation, and at the time it was the British, so I have to tip my hat to them, they did a bloody good job at it, as it still stands to the day and really needs no revision. Leave it at Greenwich, or as it's known in time circles, Coordinated Universal Time.

      Neil DeGrasse Tyson did a gentleman's job at explaining the concept during a lecture available on the web:
      - The Greeks named the constellations (while inventing the concept), so we still use the Greek names for them.
      - The great Islamic culture of a thousand years ago named the visible stars, so we still use the Arab names (Alnitak, Alnilam, Mintaka, Rigel and Betelgeuse, to name a few just from Orion). FWIW, my favorite star name is the tip of the Big Dipper's handle - Al Kaid, which means "leader of the mourning maidens".
      - The Brits invented the modern system of correspondence and postage, so their stamp is the only one that does not specify the country of origin, to this day.
      - The North Americans invented the Internet, so USA websites are dot-com, while the rest of the world uses dot-com-dot-suffix.

      All I'm saying is, in a modern world with thousands of pockets of eccentric engineers, it's comforting to find examples of global standardization, and the time zones is one of them.

      • by ThrowAwaySociety ( 1351793 ) on Wednesday October 21, 2009 @10:03AM (#29823627)

        - Video. The PAL standard is better quality than NTSC (Never The Same Color), so why did the Americas adopt an inferior option?

        That's sort of like asking why we adopted the clearly inferior analog STDV standard instead of digital HDTV. NTSC was standardized in 1953, PAL was not standardized until 1963. Naturally, PAL was the superior standard...it was based around technology that was ten years more advanced.

  • Not true for WGS84 (Score:3, Informative)

    by tomtomtom777 ( 1148633 ) on Wednesday October 21, 2009 @04:21AM (#29820787) Homepage

    It is worth noting that in the coordinate system most used today (WGS84), this is no longer true.

    See this [googlesightseeing.com] explenation or check google maps.

  • How many other Greenwich's are there at 0 longitude?

  • nuff said.

  • WTF?? (Score:3, Insightful)

    by EdIII ( 1114411 ) * on Wednesday October 21, 2009 @05:39AM (#29821163)

    he proposed a single 24-hour clock for the entire world, located at the centre of the Earth and not linked to any surface meridian.

    I have tried finding a reference to this and can't. What does it mean by being located at center of the Earth and not linked to any surface meridian? Time zones are linked to surface meridian's right? So how would a system work that was not linked to anyplace on the surface?

  • Many people forget to deal with, or at least poorly handle time zones in software. I think it would be much easier to just adapt to using a single time for the entire planet ... they're just numbers. Who cares if you need to wake up at 23:00?

    One of my favourite Jeff Atwood quotes is "All you UKers who live in UTC+0 are a bunch of dirty, filthy, stinking time zone *cheaters*".
    • by Neil ( 7455 )

      Except we mess up the simplicity by being on "British Summer Time" (daylight saving time, one hour ahead of UTC) as civil time for much of the year.

      Roll-on Sunday! (when we go back, and I get an extra hour in bed :-)

  • Anybody wondering why it's doesn't run through Paris? Take a look here [albinoblacksheep.com]

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