Luna galloped to Celestia's side, tears pouring from her eyes.  After being defeated as Nightmare Moon, she finally saw the truth.  

"I'm so sorry!" she said through her tears,"Can you ever forgive me?"

Celestia looked down at her sister with teary eyes.  She smiled a bit, glad that she had been finally reunited with her sister.  Luna felt a tear drop on her head and looked up to see Celestia crying.  But to her surprise, Celestia was biting her lip and looked as though she could barely keep from bursting out into laughter.  

Luna turned her head sideways, unsure as to what was so funny.  Celestia looked down at her and barely managed to get out words.

"To the moon!"