Fresca 16+ Sagitta Alter. Its name is latin for arrow, and it should not be confused with the significantly larger constellation sagittarius, the archer.although sagitta is an ancient constellation, it has no star brighter than 3rd magnitude and has the third smallest area of all. It was included among the 48 constellations listed by. In geometry, the sagitta (sometimes abbreviated as sag) of a circular arc is the distance from the center of the arc to the center of its base.