Note Pack 7 AIM What are time zones

Note Pack #7 AIM: What are time zones and why are they important? Do Now: Why do you think East Coast football games start at 1: 00 and West Coast games start at 4: 00?

The Shape of the Earth • The Earth is shaped like a ball or a sphere. • To go completely around the Earth, you must travel 360 o. • The Sun only shines on half the planet at a time. • But because the Earth spins or rotates is a counter clockwise or West to East direction, sunlight will touch all of the Earth in a 24 hour period.

The Shape of the Earth (cont) • The position of the Sun changes in the sky throughout the day and is different depending were you are on the planet. Example: In the morning, the Sun is rising in Brooklyn, but setting in Tokyo, Japan.

Time Zones • Time on Earth is divided into 24 hours. • Longitudes divide the Earth into 24 sections called Time Zone. • Each Time Zone equals a 15 o slice of the Earth from North to South. 15 o x 24 = 360 o

Facts about Time Zones • There are 24 time zones. • Time Zones start at the Prime Meridian, which crosses through the city of Greenwich, England. • Because Time Zones cross each other at the North and South poles, the distance between them varies depending on how North or South you are. • Time Zones are not always straight (north and South). Sometime the Time Zone is zigzagged to include territories in the same Time Zone. • The International Date Line divides the days of time. Example Monday and Tuesday.

Time Zones in the United States • The US has 6 time zones – 4 on the US mainland • Eastern • Central • Mountain • Pacific – 1 for Alaska – 1 For Hawaii

How do we use Time Zones • You can calculate the time of any city if you know the time in 1 Time Zone and the number of Time Zones you need to cross to get to the city you wish to know the time. Example 1: It is 8: 00 a. m. in Brooklyn, what time is it in Paris. 8 +6 14 It’s more than 12 so…. . Paris Brooklyn 14 -12 2 It’s 2 p. m.

How do we use Time Zones Example: It is 8: 00 a. m. in Brooklyn, what time is it in L. A. 8 -4 4 It’s less than 12 so…. . It’s 4 a. m. LA Brooklyn Going East – the day gets later. Going West – the day gets earlier

Times of other Cities in Respect to your City. • Depending of the location of other cities when compared to your location, some cities can have times that are ahead of you, behind you or the same time as you. • If the city is located East of your city and in a different time zone, the city is later in the day than your city. Example – NYC is 12 p. m. and Rome is 6 p. m. • If the city is located West of your city and in a different time zone, the city is earlier in the day than your city. Example – NYC is 12 p. m. and LA is 8 a. m. • If the city is located North or South of your city and is in the same time zone, the city has the same time as your city. Example – NYC is 12 p. m. and Boston is 12 p. m. and Miami is 12 p. m.