[HN Gopher] The Discovery of the Celendrical Date Line
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The Discovery of the Celendrical Date Line
Author : thunderbong
Score : 50 points
Date : 2024-08-21 08:32 UTC (14 hours ago)
(HTM) web link (webspace.science.uu.nl)
(TXT) w3m dump (webspace.science.uu.nl)
| TedDoesntTalk wrote:
| Wikipedia says the international date line is "a cartographic
| convention, and is not defined by international law."
|
| The "line" wasn't a convention at all in the 16th century so how
| did sailors experience loss of a day?
|
| https://en.m.wikipedia.org/wiki/International_Date_Line#:~:t....
| canjobear wrote:
| The line is the reason you don't lose a day now. When you
| circumnavigate the world westward, the earth has rotated one
| less time for you than for everyone else, so it appears you
| have lost a day. By artificially switching the day at the date
| line you avoid this kind of slippage.
| psunavy03 wrote:
| On a ship, you also keep the same time zone as local time for
| the area you are steaming through. Going consistently
| westward to get somewhere is a bonus, because every other day
| you get to sleep in an extra hour.
| PaulDavisThe1st wrote:
| Oddly enough, on the Queen Mary 2, sailing eastward from
| NYC to Southampton, they change the time just after lunch.
| No extra sleep-ins!
| brookst wrote:
| Obligatory Umberto Eco plug:
| https://en.wikipedia.org/wiki/The_Island_of_the_Day_Before
|
| Hopefully Eco + the title is enough but if it helps IMO it's
| arguably his best work. All of the stepwise logic leading to
| madness of Name of the Rose and Foucault's pendulum, a somewhat
| less slapstick sensibility than either, without descending into
| dryness as his later work. Super recommended.
| LordN00b wrote:
| A +1 for this recommenation. I particularly enjoyed this for
| how the sailor explains his situation, using the mental tools
| avilable to him at that period of time. I always enjoy the how
| author goes to great lengths to explicate a period mind set
| (Name of the Rose/Baudolino/Island/Focualts) so it feeds the
| fabric of the narrative for the reader.
| arianvanp wrote:
| I'm surprised this is still up. The UU has been on a quest of
| destroying all web pages hosted under uu.nl domain that are not
| managed by "the cloud", Office365 or blackboard with the argument
| of "its not gdpr compliant". All the old personal web pages of
| professors of the CS department (cs.uu.nl) have already been
| purged in the name of "compliance". Decades of Internet History
| and science just wiped because of somebody's career fetish. Seems
| the math department had more backbone than the computer science
| department.
|
| I wrote a bot that archived it all and it's on my old university
| laptop still. Lots of gems, blog posts, articles that were all
| just deleted. I still need to upload it somewhere
| Terretta wrote:
| > _I 'm surprised this is still up... All the old personal web
| pages of professors of the CS department (cs.uu.nl) have
| already been purged..._
|
| Then the traditional ~username URL and home page will bring
| some nostalgia:
|
| https://webspace.science.uu.nl/~gent0113/idl/idl.htm
|
| https://webspace.science.uu.nl/~gent0113/
|
| And the statcounter dating back to 2008 should make you happy:
|
| https://statcounter.com/p3895088/summary/yearly-pur-labels-b...
| fsiefken wrote:
| I wonder how the discovery of the need of this International Date
| Line influence not just navigation and timekeeping, but also the
| understanding of experience of the flow of time, did it perhaps
| influence the Englightment, as it just occured before, or was it
| the age of discovery of the Americas and the Pacific? Difficult
| to seperate.
|
| A Romanian girl called Iliana/Ilana from Galati or Brailia I was
| in love with long ago recommended me Umberto Eco's The Island of
| the Day before when I met her in Taize. Sadly I lost her contact
| data and her lastname, forever lost in the day before.
| madcaptenor wrote:
| Interestingly, the date line wasn't always where it is now. For
| example if you look at the tz database it has Asia/Manila with an
| offset of -15:56 until 1844; that's because the Philippines were
| actually colonized from Mexico, so they kept the same day count
| as the Americas. (https://webspace.science.uu.nl/~gent0113/idl/id
| l_philippines...). But as they came to be more integrated with
| their geographical neighbors they switched to counting the days
| like them.
|
| Similarly tz has time zones as far east as +15:13:42 for
| Metlakatla in far south eastern Alaska, until 1867, since Alaska
| was settled from Russia. I think these are basically the furthest
| east and west the date line ever went (although maybe the
| Russians made it further south and east along the west coast of
| North America?)
| treve wrote:
| I thought historical data in the tz database was recklessly
| deleted a few years ago. (To my horror)
| madcaptenor wrote:
| It wasn't! See https://github.com/eggert/tz/blob/main/asia
| bewaretheirs wrote:
| It was deleted from the default build of the timezone files
| but remains in the source tree; patches are accepted.
|
| Choices have to be made for usefulness vs completeness vs
| size as it's quite likely that at least one and perhaps
| multiple copies of the database are present on any system out
| there running code in C that needs to know what time it is in
| human terms.
|
| But if you're a packrat, you can include the extras in your
| build of the timezone data by setting PACKRATDATA=backzone
| during the build.
| cardiffspaceman wrote:
| > the Russians made it further south and east along the west
| coast of North America
|
| This is why there is a Russian River [1] in northern
| California. One of its names is "Slavyanka River" which was
| given by Russians.
|
| [1] https://en.wikipedia.org/wiki/Russian_River_(California)
| shepherdjerred wrote:
| I didn't realize Russia ever had made it past Alaska! The
| world would be a very different place if they were there a
| couple hundred years earlier.
| Lammy wrote:
| See also: Fort Ross
| https://en.wikipedia.org/wiki/Fort_Ross,_California
| bewaretheirs wrote:
| Russian fur traders made it to what is now called the Russian
| River in northern California in the early 1800's, founding Fort
| Ross.
| madcaptenor wrote:
| Of course! And it looks like the Spanish weren't north of San
| Francisco at the time, so the only people in the area using
| something resembling our current time system would have been
| Russians coming from across the Pacific.
|
| So the easternmost "time zone" ever is at least +15:47 or so.
| madcaptenor wrote:
| And of course Manila is not the westernmost point in the
| Philippines. Wikipedia has local mean time in the Philippines
| going from -16:12 to -15:34
| (https://en.wikipedia.org/wiki/Philippine_Standard_Time),
| although that assumes that the current Philippines have the
| same longitudinal extent as in 1844 - and I can't quickly
| figure out the history well enough to know if that's true.
| gumby wrote:
| > Interestingly, the date line wasn't always where it is now.
|
| Different empires defined their own prime meridians (and thus
| implicitly their date line 180 degrees away) from the
| ~16th-19th century. Eventually in the late 1800s a conference
| was organized to pick one and since Britain was the center of
| commercial shipping (with all the concomitant infrastructure
| like Lloyds, project finance, Admiralty law etc) there was
| little dissent.
| syncsynchalt wrote:
| I wonder if Pigafetta's account was the inspiration for the
| ending of Jules Verne's "Around The World In Eighty Days"?
| sltkr wrote:
| Spoiler alert! Some of us haven't yet finished that book.
| taylorbuley wrote:
| The 'lost day' occurred because the expedition had been traveling
| westward, in the same direction as the Sun. As they circled the
| globe, they were effectively chasing the Sun, which meant that
| each day was slightly longer than 24 hours. Over the course of
| their journey, these small increments added up to a full day.
| Thus, by the time they completed their circumnavigation, they had
| 'lost' one day compared to those who remained in one location.
|
| I like the concept of chasing the sun. That should be a metaphor.
| lainga wrote:
| During the Francoist period, the lyrics to the Spanish national
| anthem (which now officially has no lyrics) read in part
|
| _Gloria a la Patria que supo seguir,_ / _sobre el azul del mar
| el caminar del sol._
|
| _Glory to the Fatherland, who knew how to follow_ / _the path
| of the sun over the blue of the sea._
| dotancohen wrote:
| I think that it is a metaphor. Pink Floyd mentions chasing the
| sun in the song Time, and I believe that I've heard other
| references.
| toast0 wrote:
| Following the sun is perhaps a more common metaphor than
| chasing it.
| erikbern wrote:
| Spoiler alerts but this exactly the plot twist at the end of the
| book "Around the World in 80 Days" by Jules Verne
|
| https://en.wikipedia.org/wiki/Around_the_World_in_Eighty_Day...
|
| The following day Fogg apologises to Aouda for bringing her with
| him since he now has to live in poverty and cannot support her.
| Aouda confesses that she loves him and asks him to marry her. As
| Passepartout notifies a minister, he learns that he is mistaken
| in the date - it is not 22 December, but instead 21 December.
| Because the party had travelled eastward, their days were
| shortened by four minutes for every degree of longitude they
| crossed; thus, although they had experienced the same amount of
| time abroad as people had experienced in London, they had seen 80
| sunrises and sunsets while London had seen only 79. Passepartout
| informs Fogg of his mistake and Fogg hurries to the Club just in
| time to meet his deadline and win the wager. Having spent almost
| PS19,000 of his travel money during the journey, he divides the
| remainder between Passepartout and Fix and marries Aouda.
| tzs wrote:
| It is not only sailors who get confused going around the world.
| The lightning map on the WeatherBug site and in the WeatherBug
| iOS/iPadOS app gets confused if you scroll all the way around.
|
| When opened in the US the map is centered on the US. Scroll east
| to bring Europe and Africa into view and it shows lightning
| there. Keep scrolling east to see lighting in Asia and beyond.
|
| When you come all the way around and the US comes into view there
| is no lightning. Keep going east and Europe and Africa and Asia
| have no lightning.
|
| Go around east a few mores times. Then reverse direction. You've
| got to go around west the same number of times you went around
| east to get the lightning back.
|
| For US users who want to check lighting in Europe or Africa this
| probably won't cause problems. They will most likely scroll east.
|
| But for US users who want to check lighting in say Japan or
| Australia they will probably scroll west, and there will be no
| lightning. To see lighting in Japan or Australia US users have to
| scroll east past Europe.
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(page generated 2024-08-21 23:00 UTC)