Photo courtesy NASA
NASA’s image of "Earth at Night" is familiar to most Americans. The image appears on posters and postcards, and in most geography textbooks. But how was this image made? And what does it tell us about where and how we live on Earth?
First of all, "Earth at Night" is not a single image, but rather a composite of hundreds of photos taken by low-altitude satellites that are able to detect light emitted by towns, cities, industrial sites, oil fields, and fires. Careful examination of the image reveals much about the distribution of people and their activities on Earth.
Examining the Image
a) Access the "Earth at Night" image online and project the image on a classroom screen, or alternatively, if a computer lab is available, have students working in small groups access the image. Provide students with blank world regional maps and world atlases.
b) Begin by clicking once to zoom in on the United States. (Clicking a second time will return the image to full size.) Have students compare the lights on the image to maps of the U.S. in the atlas in order to identify major urban areas. Have them label these urban areas on a blank map of the U.S., identifying major cities. Ask students to explain the uniform distribution of tiny dots of light in the Plains states (the grid pattern is a remnant of the township and range survey system used to divide land parcels in this area). Ask them to explain the dark areas on the image (dark areas are mountains, desert, or other areas with little or no population). Have them refer to their atlases to identify and label these areas on their maps.
c) Assign different groups the following regions: South America, Europe, Africa, Southwest Asia, South Asia, East Asia, and Southeast Asia and Oceania. Have them repeat the exercise above for these regions, recording what they observe on the appropriate regional map.
Extending the Activity
Point out to students that not all visible light comes from urban areas. In fact, oil field burn-off flares and fires from slash-and-burn agriculture are also visible.
d) Access an updated version of "Earth at Night" and open the image. Point out the bright yellow and red areas on this image. Have students use maps in their atlases to identify these areas and speculate what the colors represent (yellow areas are oil fields; red areas are agricultural burning).
The top 10 finishers — from the field of 54 state-level winners who took part in the prelims — will compete in the final round to be held at The National Theatre in Washington, D.C., on Wednesday, May 22.
To celebrate the 25th anniversary of the National Geographic Bee, the national finals will be held in a larger DC venue with tickets available to the public. Get your tickets for the May 22 finals and see the top ten students compete live with Alex Trebek moderating.
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Alex Trebek takes to the streets of Washington, D.C. to see how well residents know their geography.
Teachers and Parents
Principals of schools in the U.S. with any of the grades four through eight are eligible to register their schools to receive contest materials for a school-level Bee.
Wondering how to register for the Bee or how to prepare? Our "Frequently Asked Questions" have the answers!
What's the best way for students to prepare for the Bee? Here are some tips from the National Geographic Bee.
Answer sample questions from the National Geographic Bee, and get ideas on how to look for clues within the questions that can help you figure out the right answers.
Quizzes to Go
Do you have what it takes to be the next National Geographic Bee Champion? Find out the fun way with the new GeoBee Challenge! Three types of game play make sure you really know your stuff and never get bored.
Google Earth Presents
A look into why geography is important to understand as students around the country prepare for the 2013 National Geographic Bee.
Teachers can use these activities in the classroom to prepare students for the bee!
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