The Moon from Major Arcana Tarot Card is a symbolic card of mystery and hidden meaning. The Moon is a card of illusion, and often suggests a time when something is not as it appears to be.
 
"The sequence of tarot trumps is almost explicable as a cosmograph, or symbolic map of the universe. The "celestial spheres" (Star, Moon, and Sun) are grouped together, just before emblems of heaven and God (the Angel and the World), reflecting the conventional understanding of the cosmic order. But there is a peculiarity: the Star appears before Moon and Sun, not after them as the wisdom of the times would have dictated.
 
Perhaps the original designers of the tarot were informed by a philosophy that regarded the feminine principle as essential (if nevertheless alien to the social norms of the time), and so they elevated the Moon above the Stars to (near) parity with the Sun, so that both male and female principles become indispensible templates for the entire created cosmos."