The Frigg Moon Pacifier | Full Of Charm! FRIGG Moon Phase is a round pacifier with a round nipple shape. The round pacifier resembles a mother’s breast in both shape and material. The explanation for this is that when the child is about to breastfed, the tongue rolls up around the nipple and creates a vacuum, which causes the milk to flow. When the child sucks on a round pacifier, it rolls its tongue around it the same way.