Spring Sun has reached his full length (Hb9-34). His head has come off like a coco and it becomes the 'cup' of the year (Hb9-36). This cup is the 2nd part of the story of Sun, and in the rongorongo system it is often indicated by 2 glyphs of the same kind, here a pair of mauga ('hidden by the mountain').

mauga

The back side is the 2nd part of Sun's voyage, but it is the 1st part of Moon's voyage. Hiro is the dark first night of Moon. She takes care of the coco. In Hb9-38 the glyph type is mama, a word which for us naturally associates to Mother.

The role of Moon is to nurture a new Sun baby to be born as Maui from the topknot of the old year.