Home > Site information > Newsletter > All the Time in the World > If It’s Tuesday, It Must Be Thursday

all the time in the worldRSS

If It’s Tuesday, It Must Be Thursday

By Allan Eastman

Go back to Page 3

Strange Times at the Date Line

Map showing the International Dateline

Above is a map showing the approximate location of the International Date Line.

The Time Zone system counts 12 hours in either direction from Greenwich and meets up more or less in the middle of the Pacific Ocean. This imaginary boundary is called the International Date Line and anywhere it meets, an extremely strange thing happens. Time jumps ahead 24 hours – an entire day.

If you paddled your outrigger canoe out from Samoa and floated along the date line pointing North, the right side of your body would be at say, noon Wednesday but your left side would be at noon Thursday. You have to agree that this is pretty weird.

This is because Time as delineated by the Prime Meridian Conference counts eastward from the International Date Line, gaining an hour as it moves through each successive Time Zone. When you finally get back to the same point all the way around the planet, you have counted 24 hours so basically, you have added a day.

Curiously, the Conference never officially defined the Date Line. In essence, it doesn’t really exist except as a matter of convenience and as an unusual phenomenon in human existence. My own opinion is that all those delegates in 1884 just couldn’t get their Victorian heads around the strange goings on at the Date Line so they just decided not to mess with it. There it was out in the middle of the Pacific Ocean where it wasn’t going to bother anyone except the odd mariner or South Sea Islander.

Nobody had conceived of international jet air travel or worldwide instantaneous communications.

In theory, the Date Line lies along the 180 degree meridian of longitude, on the opposite side of the planet from Greenwich. In fact on any general map, it jogs wildly east and west in its passage from the North to the South geographic Poles to accommodate various countries’ desires to be on one side or other of the line and hence closer in time to other places near to them. The Aleutians want to be the same time as the rest of Alaska. Just to complicate matters, the island state of Kiribati has chosen to be in the time zone to the west of it, closer to New Zealand so the date line stretches way east to take it in. So even though Kiribati is further east than Samoa, it is a day later in Time. It makes your head ache.

Back on my Jumbo jet headed for Australia, I couldn’t get over my discomfort with the whole date line experience. And when I landed and got to work on the project, it further complicated matters.

More than once , I called my Agent in LA on Monday to complain about something and was outraged to get the answering machine. Eventually, I would realize that it was Sunday in California and no one could be expected to be in the office.

A few times actors scheduled to fly in for guest parts were a day late arriving because somebody in LA had forgotten to factor in the lost day crossing the date line.

Advertising

Conference calls with the production partners were a nightmare. Two days of the business week we couldn’t talk at all because it was the weekend in one place or the other. A call from Australia at 0800 Tuesday would be connected with Los Angeles at 1500 Monday and Toronto at 1800 Monday.

Even worse, one time we decided to take a quick holiday to the Cook Islands, forgetting that we were going back eastward across the date line. We arrived the day earlier than the one we had reserved and had to scramble to find a bed for the first night.

Going east across the date line was the great plot device Jules Verne used in his classic novel, Around the World in 80 Days. By sending Phineas Fogg eastward around the planet, Verne has his hero arrive back in London in the required 80 days although for himself personally, 81 days had passed.

And so, that philosophical problem...would crossing the date line make you live a day longer or a day less in your life? Well, that’s still a hard question to answer because you have to apply a kind of relativity to it.

In fact, your body will live the same amount of time – the same number of days – but generally speaking, the dates will vary according to how many times you’ve crossed the date line. If you’ve traversed the line westward 10 times say and never returned eastward back across it, your life would be more or less 10 days longer according to the calendar than if you’d stayed at home.

In some ways, this is as close to time travel as any of us are likely to get.

Should anyone be as bemused by the Date Line paradox as I am?

Probably not.

It is just another manifestation of the mysterious nature of Time itself and of our brave but inadequate human attempts to try to codify something that refuses to be bound by definitions.

I have to admit I admire the strangeness of it.

Oh, and to close with one more prime sample of weirdness, did you know that for 2 hours every day – from 10:00 to 11:59 UTC – there are actually 3 days coexisting on Planet Earth? When it is UTC 10:15 Thursday, it is 23:15 Wednesday in Samoa and 00:15 Friday in Kiribati.

I mean, really.

Comments
  Elizabeth
I read "Longitude" by Dava Sobel a few years ago. It is amazing that the world
can pretty much, almost, with a few exceptions, agree on something so
all-affecting as time.
Submitted 2010-06-19 00:22:14
  Spark Rutherford
Great article Allan.
Submitted 2010-06-21 22:56:54
  Tommie
When flying from Sydney to San Francisco you can get there an hour before you
left. If you have a newborn baby with you will they have even been born yet? Try
explaining that to the TSA and immigation computers.
Submitted 2010-09-08 18:15:56
  Mike Buck
At first I thought that we should update the dateline to move with the
midnight hour as the earth turned. Then I realized, without a fixed date line,
the day could never change. With a 24 hour clock, it would be Thursday forever
because it could never be two days on the planet at the same time. The day would
forever be chasing the line, and if it ever let go then we would slip from
Thursday into infinity.
However, if we changed the days into 12-hour intervals, then we could have
days chasing the sun where the day would start after midnight and end at noon;
start after noon and end at midnight. We would have 14-days per week with seven
being dark and the other seven being light.
I got to tell ya, I was very confused when my wife flew to Laos and told me
it was a day later. I thought she was confused because the sun travels over me
first. But after reading this article, I realized I wasn't confused, I was a day
late, literally.
Submitted 2011-01-01 21:32:15
  tim barker
mega kool man lov'in it. keep up the good work
Submitted 2012-04-18 12:41:16
  Don Wagner
Mr. Eastman, thank you for a very good history lesson and travel log. I like
many readers am a fan of your work. Fleming was a cool dude! One thing that we
must first understand that the New Earth Day (actual date line)is moving around
the planet, just as our sun appears to move around because of the earth's
rotation. A circle has 360-degrees divided by 24-hours gives us 15-degree Intl.
Time Zones. These were fixed by International agreements at the turn of the
century, helping resolve much of the confusion imposed by the old navy system of
Captain Bowditch. One still sees these time zone maps in school books, on TV,
etc., but Intl. Time and Date are not calculated using the center of a 15-degree
zone. In the early 1900's international agreement defined that the hour for each
zone would be determined by the most Eastern meridian of the zone, thereby
resolving the mathematical conflicts and confusion. Greenwich being
Zero-degrees, it is the boundary between two of the hourly time zones (12 & 13);
but the Astronomical Day is determined by 12-noon at Greenwich, not midnight. On
the other side of the world, using International Time, the New Earth Day begins
at Midnight when Zone-01 jumps an hour into the New Earth Day. When it is noon
at Greenwich, it becomes Midnight for the first time zone (180-165 degrees). The
Intl. Date Line has become a mathematical joke and the basis for the meandering
crazy date line); while the New Earth Day begins for the 99% of the world at the
180-degree Meridian. Various Pacific Island Nations all want to be first and
they can change their 'local' time to whatever...For instance, Indian uses one
zone for their nation that covers a little over 3-Time Zones. So here's how it
works for business, TimeandDate.com, the US Naval Observatory, etc.,etc... When
it is 1 second pass Midnight at 180-degrees, the eastern most degree of Zone-24,
the New Earth Day begins for Zone-01 and the other 23-time zones are the Old
Earth Day. In the last hour of a New Earth Day, all 24 International Time Zones
are the same day, but a different hour of the day. Then the cycle starts over
again at Zone-1 (180E-165E degrees). Captain Bowditch was a brilliant Navigator,
but life in his time was very slow and he assigned letters for each zone
thinking about the hour at hand so to speak and wound up creating alphabetical
soup instead of mathematical harmony (I would have done something worse I'm
sure) but not today. Then the Navies used the center of the zone because they
shoot the sun with a sextant at noon. Made sense and they still do it that way
for tradition and practice(?), but that is Astronomical or Space-Time, not
modern global electronic date and time. When you see it graphically represented
it makes perfect sense and one can calculate time in your mind between two zones
easily if you use a 24-hour clock. I live on the east coast of the US (Z18) and
India is Zone-08. They are 10 hours ahead of New York (standard) and 9-hours
when NY is Summer Time and India doesn't observe Summer Time. Here's my url
(http://flexcomm.com/itzcs/ITZclock.htm)which uses TimeAndDate.com for the
clocks of course! On the hour the java graphic rotates and displays the current
hour for each zone.
Submitted 2012-07-26 22:39:13
  Don Wagner
I said "the eastern most degree of Zone-24" and it should have read
"the eastern most degree of Zone-01"
Now let me see if am human enough to read the captcha again.
Homer (Doh!) Simpson
Submitted 2012-07-26 22:51:21
  Misty
Why not just have one time zone? It's not 1884 anymore. Everyone in the world
could have their clocks autoupdated to the same time, The time for sunrise would
be different all over the world. Every business sets their own hours of
operation anyway, most people work in shifts, scheduling calls to my kid who
lives 10.5 hours time wise away from me.

This would also get rid of the need for Daylight savings. Businesses would be
smart enough to have different winter and summer ours if they wish it.
Submitted 2013-05-22 20:30:45
  Misty
Errr... Hours...
Submitted 2013-05-22 20:31:41
  Allan Eastman
Hi Misty - A nice idea but unrealistic, probably - I don't think any nation is
going to agree with being awake all night and sleeping all day...for sure the
present system is antiquated and unwieldy but it is hard for societies to give
up traditional systems - the US, for example still stays on old British
measurements although the entire rest of the world has gone to the metric system
- kilometers, grams, liters...maybe eventually there will be an adjustment like
making a 20 hour day or something like that...One thing that could go right away
is the whole Daylight Savings idea - a lot of countries have discarded it
already...it is claimed that it helps save energy but others say this is not
true...and pretty much everyone hates moving their clocks forward...

Thanks for your comment - much appreciated Best regards, Allan
Submitted 2013-05-23 10:39:34
  Misty
Nobody needs to stay up all night. The need for sleep and when you do it is
regulated by your body's circadian rhythms. What i mean by having just one time
zone is for everyone to tell time by either GMT or by the first timezone after
the international date line. so let's say that ann lives in the first time
zone. nothing would change for her. bill in time zone two who works at bank,
would not go to work from 9 to 5 anymore, he would clock in at 10 to 6. so when
ann and bill call each other, the call time that shows on their cell phones is
the same. lets say it is 17:00 in time zone 1. that means that it is evening
there. I, living in timezone 10, look at my watch and see that it is 17:00. for
me, it means it is morning. for my son in timezone 20, it is the middle of the
night.
Submitted 2013-05-25 18:07:10
  Alpha
Great much enthusiasm i've had of this essay. I'd have 3 weekend days.
Submitted 2013-11-21 15:24:25

Page 1 | Page 2 | Page 3 | Page 4 & Comments