MODELS OF THE EARTH

60 N 30 N

60’ Lat? Long? X 60’

Parallel lines of sight

Altitude of Polaris = latitude W 60º S N E Latitude = 60º

The entire Earth rotates 15º/hr around an axis

Time zones exist because the Earth is round

Time Zones 24 time zones 1 hour difference between each zone 15 degrees of longitude between each zone Actual zones zig zag to avoid city and state boundaries

Time gets later as you travel east Change your day when you cross midnight Earth’s Rotation

Also change your day when you cross the International Dateline West-ahead 1 day East- back 1 day Also change your day when you cross the International Dateline

U.S. Time Zones

Solar Noon: Telling time by the Sun When the sun is at its highest point in the sky at your location It’s not necessarily noon on the clock unless you live in the middle of the time zone Who gets solar noon first, Maine or New York? Who gets noon on the clock first?

Greenwich, England Greenwich Observatory Clock

To the naked eye the earth appears perfectly round

Oblate Spheroid

2 1 Which would be the best model of earth? 3

From this satellite view our Earth appears round But how could early man see evidence for a round earth ?

Evidence of Earth’s Shape Earth’s shadow A lunar eclipse

What happens to the appearance of the ship as it sails away from us?

Ships may only be placed in the open ocean on the intersection of Battleship Game Ships may only be placed in the open ocean on the intersection of Lat. and Long. lines XX = Destroyer (2) XXX = Battleship (2) XXXX = Carrier (2) May go diagonally