Why the Sky Is Blue (But Sunsets Are Red)
Sunlight looks white, but it's actually all colours mixed together. Blue light bounces around in the atmosphere, turning the whole sky blue. At sunset, light travels further and the blue scatters away — leaving only the warm reds and oranges.
An Experiment to Try: Fill a clear glass with water. Add a few drops of milk and stir gently. Now shine a torch through the side of the glass in a dark room. What colour does the light look from the side? What colour does it look from the front?
You may notice the light looks slightly different depending on which angle you view it from.
Light Is Not Just One Colour
Sunlight looks white or yellow, but it is actually made up of all the colours mixed together. You can see this when rain splits sunlight into a rainbow.
Each colour in sunlight travels in a slightly different way. Blue light bounces around more easily than red light. Scientists call this scattering.
Why the Sky Looks Blue
When sunlight enters Earth's atmosphere, it hits tiny gas particles. Blue light bounces off these particles in all directions, spreading across the whole sky. This is why, whichever part of the sky you look at, you see blue.
Red and orange light travels more straight through without bouncing as much. During the day, you do not notice it as much because the blue is so spread out.
Why Sunsets Are Red and Orange
At sunset, the Sun is much lower in the sky. Its light has to travel through much more atmosphere to reach your eyes. By the time it arrives, most of the blue light has already scattered away. What is left is the red and orange light, which is why sunsets glow those warm colours.
The same Sun. The same light. Just a different journey.
