He doesn 't know cassiopeia 's the mother of andromeda .
他不知道仙后座是仙女座的母亲。
For all but the southernmost parts of the united states , cassiopeia never sets .
除了美国的最南部，其他地方的仙后座都不会落下。
The double cluster is technically in the constellation of perseus . But to look for it , observe just off to the left and below the second star in the " w " of cassiopeia .
