★How a Text Is Organized
Grade 4 Reading Worksheet - Challenge Me
Read the text. Circle the heading that fits each paragraph.
Read this first
Bringing Back the Dark
For most of human history, people could look up on a clear night and see thousands of stars. The Milky Way stretched across the sky like a pale band of mist. Today, most people in the United States cannot see it from where they live. The problem is light pollution, and it is growing.
Light pollution is too much artificial light shining where it is not needed. Streetlights, signs, parking lots and buildings all send light into the night. Much of this light shines sideways or straight up. It bounces off dust and water droplets in the air. As a result, the sky over a city glows. That glow hides all but the brightest stars.
The problem affects more than stargazers. Many animals depend on darkness. Baby sea turtles hatch on beaches at night and crawl toward the brightest horizon. Normally, that is the moonlit ocean. Near bright hotels and roads, however, some turtles crawl the wrong way. Many birds migrate at night and use the stars to find their way. City lights can confuse them, and they may circle lit buildings until they are worn out.
People are affected too. Our bodies use darkness as a signal that it is time to sleep. Bright light at night can make it harder to fall asleep.
Fortunately, light pollution is one of the easiest kinds of pollution to fix. Unlike trash or smoke, it disappears the moment a light is changed or switched off. Towns have tried several solutions.
The first solution is to point lights downward. A shielded streetlight has a cover on top, so its light falls on the street instead of the sky. A second solution is to use only as much light as is needed. Some cities dim their streetlights late at night or use motion sensors. A third solution is to choose warmer, yellow-orange bulbs. They scatter less in the air than bright blue-white ones.
Some places have gone even further. Flagstaff, Arizona, passed one of the world's first outdoor lighting rules in 1958. In 2001, it became the world's first International Dark Sky City. On a clear night there, people can still see the Milky Way from town.
Along some beaches in Florida, towns ask people to turn off or cover beach-facing lights during turtle nesting season. In many cities, tall buildings dim their lights in spring and fall, when birds migrate.
Light pollution grew slowly over many years. With good choices, though, the dark sky can come back quickly.
Which heading best fits the paragraph that begins “The first solution”?
- Animals That Need the Dark
- How Sky Glow Begins
- Three Ways to Fix the Problem
- The First Dark Sky City
Which heading best fits the fourth paragraph?
- Turtles Crawl the Wrong Way
- Light and a Good Night's Sleep
- Stars Hidden by Bright Sky Glow
- Cities Dim Their Streetlights
Which heading best fits the eighth paragraph?
- Why Stars Fade From View
- A City Under the Milky Way
- Help for Turtles and Birds
- Pointing Lights Downward
Which heading best fits the ninth paragraph?
- Streetlights With Covers
- How Light Bounces Off Dust
- Turtles on Florida Beaches
- A Dark Sky Can Come Back
