What phase is described as not visible on Earth due to its position relative to the sun?

The new moon phase occurs when the moon is positioned between the Earth and the sun. During this phase, the side of the moon that is illuminated by the sun faces away from the Earth, making it essentially invisible from our perspective. This lack of visible illumination is the defining characteristic of the new moon, as there are no sunlight reflections bouncing back to Earth. In contrast, other phases like the full moon or waxing crescent are clearly visible due to the alignment of the sun and moon allowing light to be reflected toward the Earth.