How could Moshe raise his hand on the heaven?
Rashi #1: "Al ha'Shamayim" means (not on the heaven but) towards the heaven.
Rashi (citing the Midrash): Hashem raised Moshe above the heaven.
Sifsei Chachamim: Thereby epowering him to bring the next three Makos, which took place in the atmosphere. Refer to 9:14:2:1.