From Wikitroid, the Metroid wiki

The Sky Temple on Dark Aether is the evil, twisted version of the Great Temple. It is where the evil Emperor Ing and Dark Samus await Samus Aran at the end of Metroid Prime 2: Echoes. After Samus defeats the Emperor, Dark Aether will begin to die, and therefore whilst battling Dark Samus, the player must work quickly. The Sky Temple bears little aesthetic resemblance to its counterpart on Aether, incorporating the Ing architectural mainstays of black stone and Ingworms. The Temple is also isolated from the ground in that it seems to float high up in the air, accessable only by teleporting (maps show that it floats higher than the Ing Hive Summit). It is interesting to note that while its rooms parallel those of the Great Temple, the entire complex is upside down. It is also the smallest area in the entire game, consisting of three rooms.