Notes on Sunlight and Sky Color Changes

Introduction

• Observations of the sky color during different times of the day.
• Clear day: Sun appears yellowish, sky appears blue.
• As the Sun sets, colors change to red, orange, and yellow hues.

Nature of Sunlight

• The Sun emits white light, which consists of seven colored waves:
  • Red
  • Orange
  • Yellow
  • Green
  • Blue
  • Indigo
  • Violet
• In space, the Sun appears white due to no atmospheric interference.

Rayleigh Scattering

• Definition: Atmospheric phenomenon where light waves scatter.
• Key Points:
  • Blue light waves are shorter and scatter more effectively than red light waves, which are longer.
  • This scattering is why the sky appears blue during the day.
  • The Sun appears yellowish during the day because red and green light combine to create yellow.
  • At noon, the Sun may look white due to less atmospheric distance for light to travel.

Changes During Sunset

• As the Sun sets:
  • Light travels a longer distance through the atmosphere.
  • Blue light scatters significantly, reducing its presence.
  • Longer wavelengths (yellow, orange, red) scatter more effectively and reach our eyes.
• The deeper the Sun sets, the more pronounced the longer wavelengths become.
  • This explains the transition of colors from yellow to orange to red during sunset.

Conclusion

• Understanding the science behind light and atmosphere helps explain the colors we see in the sky.
• Encouragement to subscribe for more information on the topic.