With the discovery of Pluto in 1930, most astronomers considered the Solar System to have nine planets, along with thousands of significantly smaller bodies (asteroids and comets). For almost 50 years Pluto was thought to be larger than Mercury, but with the discovery in 1978 of Pluto’s moon Charon, it became possible to measure Pluto’s mass accurately and to determine that it was much smaller than initial estimates. It was roughly one-twentieth the mass of Mercury, which made Pluto by far the smallest planet. Although it was still more than ten times as massive as the largest object in the asteroid belt, Ceres, it had one-fifth the mass of Earth’s Moon. Furthermore, having some unusual characteristics, such as large orbital eccentricity and a high orbital inclination, it became evident that it was a different kind of body from any of the other planets.
This important measurement was made using Cassini's INMS instrument, which detects gases with the goal of determining their composition. INMS was designed to sample the upper atmosphere of Saturn's large, smoggy moon Titan. However, after Cassini's surprising discovery of a tall plume if icy spray erupting from cracks on Enceladus in 2005, planetary scientists turned its detectors to that small moon.
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'.
As discussed the Moon is a 'feeling' planet. Therefore having Moon in a Water element (Cancer, Scorpio or Pisces) will intensify the 'feeling' nature. Therefore anyone or anything that allows the nurturing quality to be used or expressed will assist you in feeling secure and at home with yourself. On a negative note this type of Moon could be clinging, possessive and controlling in a nurturing way.