Why is the Sky Blue Science Experiment

ByBrandi Jordan January 7, 2015February 8, 2020 February 8, 2020

In this Why is the Sky Blue science experiment, little learners can see for themselves how the blue wavelength is scattered faster than the red light from the sun. The simple experiment needs only a few things, but it can be a fascinating launch pad for discussions about the sky, the sun, the solar system, and even the weather. In fact, we will be featuring this experiment in our Science Sleuths: Wild Weather class!

Why is the Sky Blue? Science Experiment

Thought Question: Why is the sky blue?

Materials:

Measuring cup filled with 2 cups of water
A clear glass
Flashlight
Tablespoon
Milk
Safety goggles
Paper towels

Directions:

Put on your safety goggles and place a paper towel down on your work area in case the water spills.
Fill the empty glass halfway with water from the measuring cup.
Add one tablespoon of milk to the water in the glass.
Stir.
Shine the flashlight through the milky water* and watch as the water begins to turn blue.

*You may need to shine the flashlight up from the bottom of the glass to get the best results.

Conclusion: The sky looks blue, because the blue wavelength scatters faster than the other wavelengths in the atmosphere. At sunset, we see the red and orange sky, because the blue has already been scattered out throughout the day.

PRINTABLE COPY: YOU CAN DOWNLOAD A PRINTABLE COPY OF THE SCIENCE EXPERIMENT HERE.

If you are studying weather, you might also want to check out these weather-related resources:
National Geographic Kids Everything Weather Book
WeatherBug App
Weather Station Experiment Kit
The Kids’ Book of Weather Forecasting
All About the Weather Coloring Book
Is It Hot or Cold?: Learning to Use a Thermometer Book