Luna Secundus

After a mighty collision with Cybertron's forming mega-mountains, enough mass escaped from Earth to form into a second moon, the aptly named Luna Secundus.

Fiction

Transformers vs. G.I. Joe

At Megatron's command, one of Cybertron's mega-mountains slammed into Earth, Pax Megatronus the gouged rocks eventually coalescing into a new moon. Luna Secundus, as it came to be known, eventually became home to a cult of Megatron loyalists. The War Never Ends