Iowa Sunsets

At sunset time, the light must travel through more of earth’s atmosphere, resulting in shorter wavelength colors, like blue, being scattered away from the viewers' eyes on the surface of the earth, leaving only the longer wavelength colors to see, such as red and orange. In Iowa, there are also more particles in the air due to the large presence of agriculture. Especially around harvest time, there is an abundant amount of dust in the air which causes what are known as "harvest sunsets."

Possible Guiding, Compelling and/or Anchoring Questions

• What makes sunsets colorful?
• Why is the sky more red at sunset and more blue during the day?
• How is light reflected?

Classroom Suggestions

Students could: 

• Investigate 
  • Give students a short investigating sheet and have them fill out what they notice and what they wonder. 
• Investigation in class 
  • Create a Sunset in a Jar 
• Connect 
  • How are sunrises related to sunsets 
• Compare 
  • Pictures of sunsets in different regions with Iowa sunsets

Related Resources

• Colors of Light | Science Learning Hub: Provides visuals of different colors and their wavelengths.
• Sunset Colors in a Glass | Scientific American: This activity demonstrates how light particles are reflected.
• Why is the Sky Blue? | NASA: Provides an explanation for why the sky is blue.