This text is so different from the one in Habakkuk where the Lord does not seem to be answering. In this text it sounds like the Lord answers even before we ask! He has created a whole new heaven and earth and even a new Jerusalem where we will never cry again! By heaven, he seems to be talking about the "heavens" that we see around us as when we view the stars at night. He does not mean the heaven where we hope to spend eternity. Isaiah is talking to the people in exile telling them that the Lord is preparing the land for their return.
