Question

why did lunar eclipse form and when

Answer 1

lunar eclipse form when the earth comes b/w the moon and sun....I think

Answer 2

IA lunar eclipse occurs when the Moon passes directly behind Earth and into its shadow. This can occur only when the Sun, Earth, and the Moon are aligned (in syzygy) exactly or very closely so, with the planet in between. Hence, a lunar eclipse can occur only on the night of a full moon