How Does Colour of the Sun at Sunrise and Sunset Work?

The Sun changes colour when it rises or sets because of how light travels through the Earth's air.

Imagine you're holding a glass of water and looking at a bright light through it, the more water there is, the more the light changes. The same thing happens with the Sun in the sky.

Why It Changes Colour

When the Sun is high up in the sky, its light has to travel through less air to reach you. That means the light stays mostly white, like a bright lamp shining directly at you.

But when the Sun is near the horizon, like during sunrise or sunset, its light has to go through much more air. This extra air makes the light change colour, just like how your glass of water changes the light’s look.

The blue and purple parts of the light get scattered away by the air, leaving the reds and oranges behind. That's why the Sun looks red or orange at sunrise and sunset, it's like a warm, glowing ball of fire painting the sky!

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Examples

  1. A child sees the sun as red in the morning and wonders why it changes color.
  2. A student notices the sky turns orange during sunset and asks about it.
  3. Someone watching a sunset thinks the sun looks like a glowing ball.

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Categories: Science · sunlight· atmosphere· optics