Where on Earth are

You?

2

• Measured in degrees, minutes, seconds

• 1 degree = 60 minutes (1° = 60’)• 1 minute = 60 seconds (1’ = 60’’)

Nautical mile (nm)• 1 nm = 1’ of arc length of latitude• 1 nm = 1’ of arc length of longitude at the equator

Latitude and longitude

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Latitudes (or parallels) are parallel to the equator• 0 to +90° Northern Hemisphere• 0 to -90° Southern Hemisphere• Small circles

Longitudes (or meridians) are formed at right angles to the latitude lines

• Measured from the Prime Meridian• 0 to 360° East from the Prime meridian• Or, 0 to +180°E and 0 to -180°W• International date line• Great circles

Latitude and longitude

North Pole

60°N

30°N

Latitude 0°

Equator

30°S

South Pole

Latitude

5

Measuring latitude – North Star, Polaris

30°

Determining LongitudesNorth Pole

Reference: Prime meridian

Longitude60°W

0°

South Pole

at Greenwich

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Longitude and time • Use of clocks to record the time the Sun is at its

zenith• Greenwich Mean Time (GMT) or Universal Time• Earth rotates 15° of longitude each hour

http://www.rmg.co.uk/harrison

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Time Zones

http://www.bbc.co.uk/news/world-13334229 (Samoa changes time zone)

East Increase – West Less(1 hr per l5°)

If it 9 p.m. at Position D, what time is it at position C? Position B?

If it is 1 p.m. at Position X, at which location is the time 5 p.m.

• Look at the East Coast of the United States. The lights are already lit.

• California the sun is still visible.

Earth rotates west to east Solar time is based on the position of the sunNIGHT IS FALLING ON EARTH

This pictures shows AMERICAN CITIES at

night.

Waikiki