1. Time Zones Astronomy Unit Ch. 4.2

2. Effect of Earth’s rotation Created based on the rate at which the sun appears to move across the sky ▫Sun rises in the east & sets in the west Earth takes 24 hours to rotate on its axis  24 time zones ▫360  in one circle, so each time zone is 15  apart ▫(360  ÷24hrs. = 15  )

3. Dividing up Time Zones Starting point is the Prime Meridian which runs through Greenwich, England ▫areas to the east (right) of the P.M. are ahead of Greenwich Mean Time (GMT or UTC) by one hour per time zone ▫areas to the west (left) of the P.M. are behind by one hour per time zone over

4. How many hours apart is point A and point B from each other? A B

5. Time Zones in the U.S. The U.S. has 6 time zones: (from East to West) 1.Eastern Time behind UTC or GMT by 5 hours 2.Central Time (-6 hours) 3.Mountain Time (-7 hours) 4.Pacific Time (-8 hours) 5.Alaskan Time (-9 hours) 6.Hawaii-Aleutian Time (-10 hours)

6. Time Zones in the U.S.

7. The International Dateline Separates two calendar days at 180˚ longitude (“on the other side” of the Prime Meridian) Immediately to the left (east) is the eastern hemisphere which is always one day ahead of the western hemisphere to the right (west) The line bends in order to include all of Pacific Island Nations

8. Complete Time Zone Practice on the back of your notes with 1 or 2 neighbors!