So here you have two definitions of a blue moon but the one for a calendar blue moon does not describe the true meaning of a blue moon. Here's why:
The team of scientists used data gathered by NASA's Gravity Recovery and Interior Laboratory (GRAIL) mission, composed of a duo of twin spacecraft that circled Earth's Moon throughout 2012, each measuring the push and pull of the other as an indicator of lunar gravity.
People with 'Airy' Moon, (Gemini, Libra or Aquarius) will need to communicate to others their ideas, opinions, ideals, knowledge or beliefs to others in order to feel right about themselves. Finding out, learning and passing on information on will be nourishment for them, as well as a good conversation with like-minded or intellectual people. Curiosity and the need to know could be the thing that forces them out their comfort zone. Negatively they could be too influenced by others options, be indecisive or simply a 'gossip'.