heard about the Northern and Southern hemisphere but wants to know where
would the Western hemisphere be. In our rugby playing nations we often
refer to the Northern hemisphere nations and the Southern hemisphere
nations, but hardly ever hear of the Western or Eastern hemisphere.
Firstly, a hemisphere is one half of a sphere. In order to facilitate
navigation we used a term GMT to indicate where East and West should be
divided.It stood for Greenwich Meridium Time, Greenwich being a small
town in England. Many other nations had their own systems of dividing
the earth into sections, and for every nation, there country would be
the centre of where they divide the globe. France, China, Italy, Russia,
Greece, Portugal etc all had their own systems. And on the other side of
the globe the Polynesians had their own navigational methods.
In order to reach uniformity, it was decided that Greenwich would remain
the dividing line between East and West. It is now called the Prime
Meridian. And ofcourse the equator is where we divide North and South.
The Western hemisphere starts at 00 degrees 00 minutes 001 seconds West
and goes all around the globe to 180 degrees where it meets 180 degrees
East again.
The time zones also run on the same lines and UTC time stands for
Universal Time Coordinated. Moving West from the prime meridian every 15
degrees would take us one hour away from the prime meridian and we would
use a term UTC - 2 to say that we are in a certain time zone. By the
time we get to Tahiti we will be about 150 degrees West and UTC -10.
Going East from the Prime Meridian we add hours and South Africa is UTC
+ 2. Which means we will be 12 hours behind SA when we get to Tahiti.
Just for fun there is a place below Ghana and West of Gabon where the
equator and prime meridian meet. 00*00'000?/00*00'000?. We can call that
the middle of nowhere. All these lines and time zones are imaginary
lines and no, there is no line across the equator, although I've had
crew looking for it when I asked them if they could see it when we get
close. I prefer to use the moon and the sun as time instruments and the
stars to navigate by, it is the natural rhythm of Gaia. But the GPS does
give us a much more convenient and accurate way to fix our position.
We should be crossing the equator in the next few days, perhaps on
Sunday and our two new crewmembers, Nick and Eduan will cross the line
for the first time on a yacht.There are a few ways we make this ritual
something they will always remember and we give them a few choices. My
personal favourite is swimming across the equator which I think the two
guys will probably opt for. The other options are far more messy, but
also fun. They have to however choose well in advance, a few days at
least how they will cross the equator. We then have no idea wether they
will have to swim across during the day or in the middle of the night.
And to swim in the ocean at night is an experience as unforgettable as
you can get. Time will tell.
We are closing in on Fortaleza at speed and looks like we will make it
before the sun sets tonight. Our position at UTC -2 was
03*49'S/036*52'W. If you look on Google Earth there is a function you
can also set all the longitude and latitude lines. Latitude lines run
horizontal i.e. the equator and longitude lines run vertical .i.e. the
prime meridian. Nautical term for today we then make 'Latitude'. It
comes from the Latin word 'latitudo' which means breadth. In it's
nautical use it is a measure and is the amount by which a vessel's
position lies either north or south of the equator. Hence to allow a
person latitude is to give them scope and freedom of action.
Take care
Captain Paul
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