Questions for ‘Night lights have a dark side’


The continental United States at night, as seen from a NASA satellite in 2012. This image shows where there is a lot of artificial light at night.

NASA Earth Observatory/NOAA NGDC

To accompany feature “Night lights have a dark side”


Before Reading:

1.  How could light be like a pollutant?   

2.  How could too much light — or the wrong kind of light — affect animals’ or people’s behavior?            

During Reading

1.  What is the Milky Way, and why did it take citizens of Los Angeles by surprise in 1994?   

2.  What does the term light pollution mean?   

3.  How long does it take people’s eyes to adjust to the dark? 

4.  What are the three forms of light pollution?   

5.  What are circadian rhythms and how are they affected by light?  

6.  How can light pollution affect plants in cities?

7.  How has light pollution affected sea turtles?     

8.  What is infrared light, and why is it important in talking about light pollution?   

9.  How does the color of light affect migrating birds?  

10. What is melatonin?

11.  What connection have studies shown between light and human health?

After Reading

1.  What are two steps that people can take to reduce light pollution in their area?

2.  Studies suggest teens should reduce their nighttime exposure to smartphones and other lighted devices because of the effects that using these devices at night can have on sleep and health. But cutting back on the use of devices is difficult to do. What is one concrete step you could take to make it easier to do that?  


1. Design a study to measure the impacts of light at night in your home. Explain your hypothesis, what variables you will test, how you will test it and what data you will collect (and graph). After carrying out the study, did your data support your hypothesis?