It is quite common to hear references to people who discovered the various planets in the solar system, but it is rare to hear any reference to who discovered the moon. This is because the moon was never actually discovered.
The Moon is Older than Life
The analysis of moon rocks brought back by various manned missions to the moon has established beyond doubt that the moon is almost as old as the earth itself. The generally held belief in the scientific community is that the moon formed as a result of a massive collision between the earth and a huge meteor.
This resulted in a massive explosion of material into space. That material congealed together to form the moon, and gravity held the moon in orbit around the earth. These events took place long before the first life forms developed on earth. Therefore, the moon has been a visible feature in the sky to every creature with eyes that has ever lived.
Phases of the Moon
The earliest humans were fully aware of the presence of the moon, because the moon is, and always has existed before life. However, the moon looks different at different stages of its orbit. The appearance ranges from a thin sliver of light during the crescent moon to the full disc visible during the full moon. The way the moon differs in appearance is referred to as the phases of the moon.
It is quite probable that early civilizations would not have realized that the different phases of the moon visible in the sky were, in fact, different aspects of the same body or object in the sky. We never established who discovered that the different phases were of the same moon.