Trick question - the sky is actually the colour of whatever light it scatters. But why is the Sun yellow? The latest episode of MinutePhysics explains.
The sky appears blue to us, but the truth is it isn't really a colour at all. Our eyes only recognise it as blue because of the way that the molecules in the atmosphere scatter light.
This is because of a phenomenon known as Rayleigh scattering, which scatters more blue light than red light, therefore causing it to "bounce" into our eyes. But many people don't realise that this phenomenon also affects the way we see the Sun, and causes the "yellow ball" to change in colour throughout the day.
The latest episode of MinutePhysics explains (with the help of some clever computer colour additions and subtractions) how we end up visualising that perfect clear-sky blue, yellow Sun, and tropical sunset orange.
As Henry describes so poetically in the episode above - the sky isn't a colour at all, it's just a stage upon which all colours dance. Think about that next time you're appreciating a sunrise or sunset, and be grateful for all that scattered light hitting your eye.
Watch the latest episode above to find out more about why the sky and Sun look the way they do.