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APPLICATIONS AND INVESTIGATIONS IN EARTH SCIENCE NAME: ______

EXERCISE 21 CLASS: ______

RESPONSE FORM DATE: ______

1)  Over 2,200 years ago Eratosthenes of Cyrene calculated the circumference of Earth. Using a search engine such as Scirus, research Eratosthenes’s life and prepare a short report on how he arrived at Earth's circumference. Also, what were some other scientific contributions of Eratosthenes?

2) Use the information at this Color Landform Atlas of the United States Website to determine as accurately as possible the latitude and longitude boundaries of your home state.

NOTE: Use this Decimal Degree Converter to convert the decimal degrees shown on the map into degrees, minutes, and seconds.

3) Using this online atlas, accurately determine the latitude and longitude of each of the following places.

a) Cape Town, South Africa

b) Seoul, Korea

c)  Your home state's capital

4) According to the information at their Website, what is the mission of the National Geodetic Survey?

5) Use this great circle distance calculator to determine the great circle distance between Chicago, IL, and Sydney, Australia, in both miles and kilometers.

6) In addition to latitude and longitude, a second global coordinate system in widespread use is the Universal Transverse Mercator (UTM) grid.

Beginning at this Website by Sam Wormley of the Educational Observatory Institute, and, if necessary, using a search engine such as Scirus, research the UTM grid. When you have completed your investigation, write a short description of the UTM system in the following space.

Also, using the online converter at this Canadian Geodetic Survey Website, convert the latitude and longitude coordinates of your home city into UTM coordinates.

(NOTE: Print and attach a copy of the calculated coordinates page from the Website to this form.)

7) Although originally developed to meet military needs, the use of satellites for accurately determining location on Earth has spread to ships, aircraft, construction, mapping and surveying, emergency vehicles, and automobiles, to name a few applications. Today, the Global Positioning System (GPS) is an integral part of many activities and its use widespread (i.e., accessed via cell phones).

To aid in your understanding of the GPS, review the two Websites below, write a brief description of the GPS, and then answer the following questions.

1. What is a GPS? How Does it Work?, hosted by the Library of Congress

2. GPS Primer, hosted by the Aerospace Corporation

What are the three elements of the Global Positioning System?

When was the first GPS satellite launched?

What is the purpose of the control segment of the Global Positioning System?

How many satellites are used to determine a single GPS fix?

In addition to location (x and y coordinates), what other information can be obtained from a GPS fix?