Mochi IsleWhy is the sky blue?
In short: Sunlight is a mix of colours. As it passes through the air, blue light is bounced in all directions by tiny air molecules far more than red light, so scattered blue reaches your eyes from every part of a clear sky.
How it works
Sunlight looks white, but it is really a mix of red, orange, yellow, green, blue, violet and more. The air is full of countless nitrogen and oxygen molecules, which are extremely small.
When light hits these tiny molecules, it bounces off in a new direction. This is called scattering. Blue and violet light scatter the most, while most red light passes straight through. So whichever way you look, scattered blue light comes into your eyes.
Why is the sky not violet, then? Violet scatters even more, but sunlight contains less violet to begin with, and our eyes are much less sensitive to violet than to blue. So we see a blue sky.
Where to see it in New Zealand
Much of New Zealand has clean air, so a clear sky is often a deep blue. High in the mountains, such as the Southern Alps, there is less air above you and the sky looks darker and bluer still.
Try it together
On a sunny day, stand with your back to the sun. Look high in the sky on the side away from the sun, then near the horizon. Is the sky a deeper blue up high and paler near the horizon? Never look straight at the sun.
Kids also ask
Why is the sky paler near the horizon?
When you look towards the horizon, you look through much more air. The light is scattered again and again until the colours mix back together, so the sky there looks whiter and paler.
What colour is the sky on the Moon?
The Moon has almost no air, so nothing scatters the sunlight. Even in the daytime, the sky on the Moon is black.
In the game, “Blue sky” is a nature card from the Sky set, and it can turn up on any island.
Your child finds this card by reaching the right place or meeting the right weather on the island, and lights it up by answering the question on the back. Tap the button below and the game shows your child which island it is on and how to find it. Mochi Isle is a browser learning game for ages 5 to 18; the main island and the daily lesson are free.
Find “Blue sky” on the island ↗ All cards in the Sky set