When were the stars made?

How can they “sing for joy” (Job 38:7) at the creation of the earth on Day 1 if they were created on Day 4 (Genesis 1:16-19)?

God asks Job this question: “Where were you when I laid the foundation of the earth? Tell Me, if you have understanding, Who set its measurements? Since you know. Or who stretched the line on it? On what were its bases sunk? Or who laid its cornerstone, when the morning stars sang together and all the sons of God shouted for joy?” (Job 38:4-7).

Frankly, I am surprised that the question is not “how can stars sing?”

The first part of the answer regarding the stars is found in the figurative language itself, a kind of language we use daily. If I were to ask, “Who won Super Bowl XLV?” the answer would be a representative name (The Packers) instead of the roster of those who actually played in the game for the winning team? MSNBC says the Packers Beat the Steelers—did they really? Is everyone ok? What did they beat them with? The article also says the quarterbacks played on the “biggest stage.” Silly me. I thought they played on a field.

Clearly, “the morning stars” refer to something else. Given the repetition of figurative language here and in other places, this choir are identified to be the “sons of God.” Specifically, angels.