Saying something that is obvious, that didn't need to be said, and someone pointing out, wow, well done. Another comon term linked to this is also 'No Shit Sherlock!'
Something that you refer to somebody as after they have stated an obvious fact; the captain of obvious. can be used in contexts as...
1. "Thank you captain obvious."
2. "Captain obvious strikes again!"
3. "thanks for the imput, captain obvious"
1-"Check out the sky"
2-"yea...it's blue"
1-"Thank you captain obvious"