Chat with us in Facebook Messenger. Find out what's happening in the world as it unfolds.

what is a blue moon jennifer gray weather orig_00001320
what is a blue moon jennifer gray weather orig_00001320

    JUST WATCHED

    What is a blue moon?

MUST WATCH

What is a blue moon?

July 31st, 2015 marks a rare blue moon. CNN's Jennifer Gray explains the phenomenon, and why it only happens once in a blue moon.

What is a blue moon?

July 31st, 2015 marks a rare blue moon. CNN's Jennifer Gray explains the phenomenon, and why it only happens once in a blue moon.