As we all know, it is our expectation that Yang Liwei will become a space hero. The former as is only an attributive clause, which can be put at the end, that is, it is what we expect to become Yang Liwei and a space hero, as we all know. As it is directed by AS, he can plan ahead. The appositive here refers to the fact that Yang Liwei has become a space hero, which is an appositive clause guided by this fact. I hope it helps you.