The sky is blue. The ocean is, too. But the reasons why are very different.

If you’ve ever been curious about the world you live in, you’ve probably wondered why the sky is blue. It’s a question that most children ask at some point in their lives, but the answers that adults give them often don’t align with our physical reality. Some of the more common incorrect answers that people often give in response include: that sunlight has a blue tint, that oxygen itself is a…