Sophie got up and looked at the sky, searching for Polaris. It didn't take long for her to find the brightest star and, obviously, Little Dipper. She smiled and held the nocturnal above her head, in a way she could see Polaris through its hole. Turning the pointer arm around, she moved it until it was pointing in the direction of Kochab, the other star of Little Dipper.

Lowering the nocturnal, Sophie checked in the book to see if she had done it right before looking to the time the object was now showing. She hoped she had pointed the arm thing in the direction of the right star.
Yep, it seemed she did it all right! She finally stared at the nocturnal to see what time it was marking. 10:30pm. Hmm...

Sophie put her things away quickly and ran back to Hufflepuff's Common Room, to check if the time she had seen in the nocturnal was right.