What is the sky?

Question

What is the sky?

Answer 1

It's open space. There is no blanket covering earth, it's just nothing. You can't see the other planets because they're too far away. Why is it blue? It's the reflection of the sun hitting the ocean that hits the sky. When the sun goes down, it's not blue anymore. It's like when the sun hits a mirror that's tinted red it leaves a red reflection on whatever's in front of it. It's not an object..The sky is just open space...

Answer 2

It's the atmosphere.

Answer 3

The blue in the sky is the sun reflecting off of the ocean I do believe.  Kind of a vague question, kind of a vague answer.