Photo: Earth lights

Photo courtesy NASA

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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).

School Registration

Join 11,000 schools and participate in this year’s National Geographic Bee. Get a notification to alert you when registration opens in August.

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About the National Geographic Bee

Each year thousands of schools in the United States participate in the National Geographic Bee using materials prepared by the National Geographic Society. The contest is designed to inspire students to be curious about the world. Schools with students in grades four through eight are eligible for this entertaining and challenging competition.

The national championship preliminary rounds took place on Monday, May 23, in Washington, D.C. The national championship final rounds featuring the top 10 finalists and moderated by humorist, journalist, and actor Mo Rocca were held on Wednesday, May 25, at National Geographic’s Washington, D.C., headquarters.

The national champion receives a $50,000 college scholarship, a lifetime membership in the National Geographic Society, and a Lindblad expedition to Southeast Alaska provided by Lindblad Expeditions and National Geographic.

Watch the 2016 National Geographic Bee Finals

The National Geographic Bee aired on the National Geographic Channel on Friday May 27, and may still be available via streaming services. It is also airing on public television stations; check local television listings for dates and times.

Meet the 2016 Champions

National Geographic Bee contestants aren't just geography geniuses. They're also savvy park planners! See where they would create a National Park in their own state.

Host Mo Rocca interviews the Top 10 Finalists on stage during the 2016 competition.

How to Help

  • Photo: Geo Bee Winners

    Fund a School

    Donations help fund schools to participate in the National Geographic Bee.

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