Determine what fraction of stars visible to the naked eye you can see from your location. This exercise is best done outdoors with a laptop computer or through a window at night in a very dark room....

Determine what fraction of stars visible to the naked eye you can see from your location. This exercise is best done outdoors with a laptop computer or through a window at night in a very dark room. On a dark, clear night, run Starry Night Enthusiast™. On the Menu, select View Hide Daylight. Open the Options side pane, then Local View, and click on Local Light Pollution. Place the cursor over the words Local Light Pollution and click on the Local Light Pollution Options button that appears. Slide the pollution level bar until the view matches your night sky. The goal is to estimate what fraction of the visible stars you are seeing compared to the total number of stars you could be seeing under ideal conditions. Carefully do the following on the screen: Using a roughly 8 cm (3 in) square section of the sky on the screen (a square about half the length of a typical pen on each side), count and record the number of stars with your present setting. Now set the Local Light Pollution to less (which essentially gives you ideal conditions) and repeat the count of visible stars. Divide the first number you count by the second. What fraction of the stars were you seeing? To see how much light pollution occurs in large cities, adjust the slide bar in the Local Light Pollution Options to the far right, for maximum light pollution and repeat the star-counting within the same limited sky region. What fraction of the stars are large city viewers seeing?