8th Period Kaser

In lines 97-98 it says, "He went to the window and threw it wide open.  There was not one star in the sky. He went back and sat down by the table."  What was the author's purpose in pointing out that there weren't any stars?

the author's purpose of pointing out that there were not any stars in the sky was because the stars not being there resembled how he was hiding his true identity from Javert