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```									            Where am I?
• N39.797013 degrees, W84.126885 degrees
Know the four elements of navigation.
State how to determine position using latitude and
longitude
State how to determine direction using cardinal
directions and compass rose degrees
State how to determine distance both in nautical
and statute miles
State how to determine time based
on distance and speed traveled
Points on a Map Assignment
• Lines of reference are necessary in order to locate
specific points on the Earth.
•   Latitude is expressed as
either north or south of the
equator in degrees up to 90,
and longitude is expressed
as either east or west and is
expressed in degrees up to
180.
– A degree (o) of arc may be
subdivided into smaller
units by dividing each
degree into 60 minutes (’)
of arc.
– Each minute may be
further subdivided into 60
seconds (”) of arc.
– Smaller areas can be
located by going beyond
degrees and minutes and
using seconds.
Position
• Longitude
•   The Greenwich Meridian is
sometimes called the first
or prime meridian,
although it is actually the
zero meridian.
• Longitude is counted east and
west from this meridian
through 180o.
• The Greenwich Meridian is
the 0o longitude on one side
of the Earth; and, after
crossing the poles, it becomes
the 180th meridian.
• These designations define the
Eastern and Western
Hemispheres.
What is the step by step procedure for finding
the absolute location of a place on the earth?

(north or south) 3. Determine the distance (in degrees) Then do the
longitude: 1. Go to the Prime Meridian 2. Determine your direction (east
or west) 3. Determine the distance (in degrees) Find the intersection of
these two lines for the absolute location.
Where am I?
N39.797013 degrees, W84.126885 degrees
Where am I?

N30 degrees W 60 degrees
POP QUIZ

5 QUESTIONS
Which letter is located at 50 degrees
north and 120 degrees east?
0 degrees latitude, 0 degrees longitude, the
intersection of the Equator and the Prime
Meridian, would be located in which ocean?
What continent would you be on at
10 degrees south and 70 degrees
west?
An airplane crashes at 40 degrees north
and 60 degrees east. What letter would
you travel to to hunt for survivors?
sinking at 20 degrees south and 100 degrees
east. What ocean would you travel to to try to
rescue the people?
POP QUIZ REVIEW
Which letter is located at 50 degrees
north and 120 degrees east?
0 degrees latitude, 0 degrees longitude, the
intersection of the Equator and the Prime
Meridian, would be located in which ocean?
What continent would you be on at
10 degrees south and 70 degrees
west?
An airplane crashes at 40 degrees north
and 60 degrees east. What letter would
you travel to to hunt for survivors?
sinking at 20 degrees south and 100 degrees
east. What ocean would you travel to to try to
rescue the people?
Direction
• Direction is the
position of one
point in space,
relative to another,
without reference
to the distance
between them.
• The points of a
compass are not
It has been
replaced, for the
most part, by a
numerical system.
DIRECTION KNOCKOUT!!!
Direction
• Since determination of direction is one of
the most important parts of the navigator’s
work, the various terms involved should be
clearly understood.
• Course – Where I want to go
• Heading – Which way I am pointed when I
travel
• Track – Actual path I follow
Distance
• Measured by the length of a line joining two
points. In navigation, the most common unit
of measuring distance is the nautical mile.
• The nautical mile is about 6,076 feet.
• Equal to 1 minute of arc on a meridian, which
is 1 minute of latitude.
• To convert nautical miles to statute miles, the
nautical mile figure can be multiplied by the
factor 1.15.
• To convert statute miles to nautical miles,
multiply the statute miles by 0.87.
Time
• The Earth makes a complete rotation of
360o during a 24 hour day.
• Zone Time
• Before the establishment of zone time in 1883,
every city and town had its own time.
• Each time zone is 15o of longitude (1 hour of
angular measure) in width, and the first zone
centers on the prime meridian.
• The United States has four standard time
zones (in the contiguous states).
Time
• Greenwich Mean Time
• The use of Greenwich Mean Time (GMT)
avoids the necessity of considering time
zones.
• GMT is the time of day at any given moment
at Greenwich, England.
Summary
1.   Earth’s Size and Shape
2.   Position
3.   Direction
4.   Distance
5.   Time

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