Astrology themed Evocation Wizard

Hey everyone I was invited to play in a DnD Campaign (havent played the game itself yet only did a little research here and there) and I was wondering if I could play an Evocation Wizard who has more of a Astrology flavor? Specificly Stars and Moon (maybe the sun as well). If that works does anyone have an Idea on how I could flavor him and his spells? Any help would be greatly appriciated.