Transcript Latitude and Longitude

Latitude and Longitude
• A coordinate system that allows you to pinpoint
your location on Earth.
• The system involves lines running in two
directions across the earth to form a grid.
• You need 2 numbers to pinpoint a spot, just like
on a graph.
Latitude
• These lines run east to west, but measure
north and south of the equator.
Latitude lines are
also called
parallels
Latitude
• The equator is the starting or reference line.
• The unit for latitude ill be N or S for north or
south
ex: 42oN or 68oS
• Latitude lines start a 0o (the equator) and end
at 90oN or 90oS (the north or south pole.
Important Latitudes
90°N (North Pole)
Northern
Hemisphere
0° (Equator)
Southern
Hemisphere
90°S (South Pole)
Longitude
• These lines run north to south, but
measure east and west of the Prime
Meridian.
Latitude lines are
also called
meridians
•
Longitude
Longitude lines are also called Meridians.
• Longitude lines meet at the poles they are not parallel.
• Distance between lines is 0 at the poles and is greater
at the equator.
• Longitude lines start at 0o (the Prime Meridian) and
end at 180o (the International Date Line)
• The Prime Meridian runs through Greenwich,
England
• The International Date Line runs through the Pacific
Ocean.
Important Longitudes
0° (Prime Meridian)
Western
Hemisphere
Eastern
Hemisphere
Latitude can be found using the
North Star (called Polaris)
• Polaris (The North Star) is located directly
above the North Pole.
• Polaris is the only star in the sky that is not
affected by earth’s rotation.
• Centuries ago sailors discovered that if you
measure the altitude of Polaris, it tells you
your exact latitude.
Latitude can be found using the
North Star (called Polaris)
• The latitude of any point in the Northern
Hemisphere is equal to the altitude of Polaris at
that location
• So latitude is determined by the star Polaris
• If you move due east or due west the altitude of
Polaris does not change, so neither does your
latitude.
Altitude of Polaris Example #1:
What latitude is this dude at?
Answer:
55°N
55°
To Horizon
Altitude of Polaris Example #2:
What latitude is this dude at?
Answer:
42°N
42°
To Horizon