Name: ________________
Date: _______
Mr. DeLeo
Period: ____
Earth’s Time Zones
Goal: Students will understand why humans
have developed time zones on Earth, and how
to figure out time at different positions on
Earth.
Background: One of the first things people
noticed when they traveled across Earth’s
surface was that the positioning of the Sun
would change as a person traveled east or
west. This caused the time of sunrise, sunset,
and solar noon to change as a person traveled
east or west. Today, we know this happens
because the Earth has a spherical shape, and
12 PM (noon) will only occur at one longitude
at one time. For this reason, humans created
time zones in order to ensure each location
experienced solar noon (sun at its highest
point in the sky) at roughly 12 PM (noon). In
the United States, we know that if it is 12 PM
(noon) in New York (Eastern Standard Time),
it is only 9 AM in California (Pacific Standard
Time), and various other times around the
world. In total, there are 24 time zones, each
with a width of 15 degrees, because Earth
rotates on its axis 15 degrees per hour.
Time Zones In The United States
Time Zones On Earth
Directions: On the following page is an image provided by Google Earth, showing a top down view
of the Earth, with the North Pole at the center. The Prime Meridian is drawn, and as we know
has a longitude of 0 degrees. Using a protractor and your knowledge of time zones, accurately
create all the time zones around the Earth. Remember, each time zone should be 15 degrees
wide, with a total of 24 time zones on Earth.
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Questions:
Use the maps in your Earth Science Reference Table to answer the following questions. Show all
work.
1. The time is 5 PM in New York ( 75°W). What time is it in Greenwich, England (0°)?
2. The time is 3 AM in Alaska (150°W). What time is it in New York (75°W)?
3. The time is 10 PM in Australia (150°E). What time is it in New York (75°W)?
4. If the time in one location is 1 PM, and the time in another location is 9 AM, how many
degrees longitude are in between these two locations?
5. If it is 12 PM (noon) in New York, what longitude would be experiencing 12 AM (midnight)?
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Practice Regents Questions
1. Base your answer to the following question on passage and time zones map shown
below.
Time Zones
In 1883, Earth was divided into 24 time zones. The United States (excluding
Alaska and Hawaii) has four time zones, which are indicated by different
shadings on the map.Each zone is roughly centered on lines of longitude that are
15° apart. These lines are shown as dashed lines on the map. Most locations within
a time zone have the same time.This time is called standard time. As you move to
the west, the time in each zone is one hour earlier than the previous time zone
When it is 1 a.m. in New York City, what time is it in Denver?
2. Base your answer to the following question 4. Base your answer to the following question
on the map below which represents a view
on The diagram below represents the
of the Earth looking down from above the
direction of Earth’s rotation as it appears
North Pole (N.P.), showing the Earth's 24
from above the North Pole. Point X is a
standard time zones. The Sun's rays are
location on Earth’s surface.
striking the Earth from the right. Points
A, B, C, and D are locations on the Earth's
surface.
The time at point X is closest to
Areas within a time zone generally keep
the same standard clock time. In degrees
of longitude, approximately how wide is
one standard time zone?
A) 7 º
B) 15º
C) 23 º
D) 30º
3. The time required for one Earth rotation
is about
A) one hour
B) one day
C) one month
D) one year
A) 6 a.m.
B) 12 noon
C) 6 p.m.
D) 12 midnight
5. Base your answer to the following question on
the United States time zone map shown below. The dashed lines represent
meridians (lines of longitude).
The basis for the time difference between adjoining time zones is Earth's
A) 1° per hour rate of revolution
B) 1° per hour rate of rotation
C) 15° per hour rate of revolution
D) 15° per hour rate of rotation
6. Base your answer to the following question on Letters A, B, C, D, and X on the
map below represent locations on Earth. The map shows the latitude-longitude
grid.
Solar time is based on the position of the Sun. If the solar time is 1 p.m. at
location X, at which location is the solar time 5 p.m.?
A) A
B) B
C) C
D) D
7. Base your answer to the following question on the map below. Letters A through
F are locations on Earth’s surface.
When solar time at location E is 12 noon, solar time at location A is closest to
A) 6 a.m.
B) 8 a.m.
C) 12 noon
D) 4 p.m.