# Places on the Planet: Latitude and Longitude

Source: Geological Society of America, 2006. Adapted with permission.

### Background

You may have seen or used Global Positioning System (GPS) devices in cars or on camping trips. These devices use data from satellites orbiting the Earth to locate places on our planet. GPS devices describe the locations to us in the form of latitude and longitude coordinates.

Citizen scientists involved in the Geological Society of America's EarthCaching project (http://www.earthcache.org) use GPS technology and latitude and longitude coordinates to find special places on the Earth. This activity will help you learn how to find locations using latitude and longitude.

### Materials

For a group of four:

• Orange
• World map or globe
• Pencils and black marker
• Index cards
• Internet access

### Procedure

1. Imagine that your orange is the Earth. You live somewhere on its surface, so put a black marker dot somewhere on the orange to signify this. How could you communicate to someone exactly where you live? Discuss with your group.

2. Now, look at the map or globe. What is drawn on this representation of the world that can help you find places on the planet? Locate the lines of latitude that run east and west around the world. Where is 0 (equator)? As you go from 0 latitude northward, what happens to the numbers? Where are the highest latitudes?

3. Now, locate the lines (meridians) of longitude that run from north to south on the map or globe. Where is 0 degrees longitude (Prime Meridian)?

4. Find where you live on the globe or map. What is the latitude there? If it's north of the equator, you read the latitude as so many degrees "north." What is the longitude? If it's west of the Prime Meridian, you read it as so many degrees "west."

5. Locate the country that is 35 degrees N latitude and 25 degrees E longitude. What body of water surrounds this country? If possible, look up this country on the Internet and find out who lives there, as well as and something about the country's history and culture.

6. Locate a country you would like to visit, and write down its latitude and longitude on an index card (don't include the name of the country). Trade your card with another person, and locate that person's country. Check with each other to see if you located the countries correctly. Research your country online, and trade what you find out with your partner.