Splitting Latitude and Longitude

1. Splitting Latitude and Longitude • 10 (degree) = 60’ (minutes) • 1’ (minute) = 60” (seconds) • Therefore: 43.50N = 430,30’N 75.250W = 750,15’W 43.750S = 430,45’S

2. Finding your Latitude • The Altitude of Polaris (North Star) is equal to the Latitude of the observer!! • Altitude - Angular distance of an object above the horizon. • Horizon - Where the sky and ground appear to meet (Altitude = 00). • Zenith - highest point in the sky, directly above your head (Altitude = 900).

3. Shape of the Earth • Oblate Spheroid - (nearly a perfect sphere) Slightly flattened at the poles and buldging at the equator.

4. Observations for Earth’s shape • Changing altitude of Polaris (North Star) as one traveles north or south. • Stronger gravity measurements at the poles. • Photographs of Earth taken from space. • Ships and planes “sinking” at the horizon.

5. Globe Measurement Activity **Roundness ratio =Polar circumfrence Equatorial circumfrence **less than 1.0 = Not a perfect sphere!