The new moon cannot be seen because it is positioned between the Earth and the Sun, making it invisible from Earth. This occurs during the lunar phases when the moon is in its crescent phase, which is the initial stage of the moon's cycle. During this phase, only a small portion of the moon's illuminated side is facing the Earth, making it appear dark.

The reason for this is due to the moon's orbit around the Earth, which is not a perfect circle but an ellipse. As the moon orbits, it goes through different phases, which are determined by its position relative to the Earth and the Sun. When the moon is on the opposite side of the Earth from the Sun, it is in a phase known as the new moon. At this point, the sun's light is shining on the side of the moon facing away from Earth, and the side facing Earth is in shadow.

Data from NASA's lunar observations confirm that the new moon phase occurs approximately every 29.5 days, which is the time it takes for the moon to complete one orbit around the Earth. During this time, the moon goes through all its phases, from new moon to full moon and back to new moon again. The new moon phase is the only time when the moon is completely unilluminated from Earth's perspective, making it invisible.

The visibility of the moon during its various phases is also influenced by the angle at which sunlight hits the moon's surface. During the new moon phase, the angle is such that the sunlight is not visible from Earth. As the moon progresses through its phases, the angle changes, allowing more of the illuminated surface to be visible. This is why the moon appears as a crescent, half, and eventually a full moon as it continues its orbit.