What is a zyzygy?

Answer 1

A ZYZYGY is when the earth, moon and sun are all in a straight line.

Answer 2

A zyzygy is a rare astronomical event where three celestial bodies align in a straight line. This alignment can involve the Earth, the Moon, and the Sun, or other celestial bodies. Zyzygy is a term used more often in literature and poetry than in scientific contexts.