It's a beautiful day

The song called "Someday we'll know" get stuck in my mind!
Anyway it just suits my day pretty well. Here's some part of lyrics that i like.
"I bought a ticket to the end of the rainbow,
i watched the stars crash in the sea, true love is one in a life time, why aren't you here with me?
Someday we'll know if love could move a mountain,
Someday we'll know why the sky is blue....."