Boating and Sailing.pdf - Moja ladja

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Part 3: Getting from Point A to Point B: Marine Navigation
arbitrarily runs through Greenwich, England. (Guess who made up the system?) From
there, meridians or imaginary lines from pole to pole mark off the degrees east or west of
the line.
The International Date Line
Yes, it’s true that the International Date Line is a great name for a pickup bar in Switzerland.
However, that’s not what we’re talking about here.
The numbers on longitude lines go up to 180 degrees in each direction. They meet at the
International Date Line, which runs through the mid-Pacific.
Traveling west, every 15 degrees of longitude lengthens the day by one hour, while traveling
east the same amount shortens the day by one hour, which is why there are different
time zones worldwide. Where the zones meet, east of the line is designated as one day
earlier than west of the zone. The name for this line is—yep—the International Date
Line.
Avoiding Platitudes About Latitudes
Latitude lines begin with zero at the equator and rise as they proceed toward the poles.
Those north of the equator are designated north latitude, those south as south latitude.
Latitude lines are spaced 60 nautical miles apart. And one nautical mile is 1 /60 of the distance
between latitude lines, designated as a “minute” of latitude.
“X” Marks the Spot
The crossing of latitude and longitude lines provide a precise means of navigation.
Particularly now that satellites linked to electronic reading devices can instantly measure
the location of any spot on the globe, the latitude/longitude system makes for very precise
navigation even in open ocean.
The latitude/longitude numbers correspond to the numbers you see on an electronic
machine called a Global Positioning System (GPS), so they show your exact position on
the chart.
A Fading Acronym—LORAN
LORAN is the acronym for the Long Range Navigation system in U.S. waters, based on a
network of radio towers that send out directional signals over coastal areas.