Observation #1

My first observation was the amount of light pollution. If you have ever lived in a city, you may have noticed and wondered why it was hard to see the stars at night. This is because of light pollution. Cities have so many bright lights shining in every direction, even up at the sky. This brightens the sky and makes it harder to see the stars. The lights also destroy the rhodopsin (a pigment that gives us night vision) in our eyes. This causes us to be able to see very few stars.

What can we do about this?

There are many things we can do about this. One thing we can do is change the street lights' lightbulb color to red. In an experiment I conducted, I figured out that red light spreads the light over a larger area, which means there wouldn't be a need for as many lights. (Below is the data from the experiment.) The light isn't as bright, so it won't brighten the sky as much. The red light also doesn't bleach rhodopsin as quickly; it bleaches it at a very slow rate.

Another thing we can do is put shields on all street lights. Since we don't need light pointed up at the sky, this will get rid of unneccessary light. The sky will be darker, and we will be able to see more stars. There are many different types of shields that work, and you can even make it yourself. If it is bought, you can buy it from stores like Home Depot and Volt Lighting. There is a wide range of prices, but most are $100 or less. Of course, you can get fancier ones for a higher price.

What I Learned/Questions I Still Have

I learned what rhodopsin is, and I learned that red light doesn't affect it. One question I still have is: How many more stars can you see with a red light compared to a yellow light?

Referenced Sites

Volt Lighting

Home Depot