1. Longitude and Latitude
Earth is divided into imaginary lines of longitude and latitude measured in degrees (since Earth is spherical). These lines form Earth’s coordinate system and enable us to locate any position on Earth’s surface.

2. Directions
Compass = tool that uses Earth’s magnetic field to locate magnetic North
Label the compass rose with the appropriate directions NW NE W E SE SW S

3. Latitude
Imaginary lines that run horizontally (east-west) across globe
“Ladder-tude” = look like rungs of a ladder
Also called parallels because equal distances from each other
North Pole = 90⁰N Latitude (max latitude)
South Pole = 90⁰S Latitude (max latitude)
Equator = 0⁰ Latitude  Divides planet into Northern and Southern Hemispheres
Latitude in the Northern hemisphere is determined by the altitude of the North Star, Polaris.

4. Lines of Latitude Tropic of Cancer 23.5° N. Equator
Tropic of Capricorn
23.5° S.

5. Finding Polaris and Ursa Minor
To find the star Polaris and the constellation Ursa Minor, locate the two end stars in the cup of the "Big Dipper."
Connect a line through these two stars. This will point to the star Polaris.
Polaris is in the constellation Ursa Minor. Ursa Minor is better known as the "Little Dipper."
Polaris will not be an extremely bright star, but it will be located due North.

6. Longitude
Imaginary lines that run vertically (north-south) across globe
Converge at the poles and are widest apart at the equator
Also called meridians
Prime Meridian = 0⁰ Longitude – runs through Greenwich, England
International Date Line = 180⁰ Longitude in Pacific Ocean (max longitude)

8. To find the difference in hours between local time and Greenwich time:
Multiply the difference by 15° per hour (The rate at which the Earth rotates)
If local time is earlier than Greenwich time, then your position is West Longitude.
If local time is later than Greenwich time, then your position is East Longitude.

9. Example
There is a 5 hour time difference between New York City and Greenwich, England. What is the longitude of NYC? (Local Time in NYC is earlier than Greenwich)
Step 1: What is the time difference? _______
Step 2: Multiply difference by 15⁰: _______
Step 3: West or East? _________
Answer: __________
5 hrs
5 x 15 = 75o
75° West Longitude
West
75o W

10. A tougher example: 35oN, 120oW
2. It is 12 noon at the Prime Meridian. You are on a boat where it is 4:00 am. You look up at the sky and determine the altitude of Polaris to be 35°. What is your latitude and longitude?
Latitude: ALtitude of Polaris = LAtitude of observer  35oN
Longitude: 8 (time difference) x 15o = 120o W
35° N; 120 ° W
35oN, 120oW