Abraham and the Astrologers
In Matt 2 the astrologers see the star that leads them to Christ. Clearly, that has an Isaianic context. In Matt 1, there is an allusion to Isaiah 7 concerning Immanuael. In Is 7:11, YHWH says, “Ask a sign of the Lord your God; let it be deep as Sheol or high as heaven.” Thus, the star is the sign in heaven.
Another important allusion is to Gen 15 where God brings Abraham outside and says, “Look toward heaven, and number the stars, if you are able to number them. Then he said to him, So shall your offspring be.” The striking thing is that seven verses later, in the same narrative unit, we are told that “As the sun was going down…” Thus, when Abraham looked up in the heavens it was day and he only saw one star.
I think this is also connected to the Day of the Lord theology. The sign in heaven, the star, the sun of righteousness rises not only on the Day of the Lord, but he precisely is the Day. As the star, he creates the eschatological Day.
Also, there is nothing in Matt that says the astrologers saw the star at night.