Avenger — William Woodall

The survivors of Earth have settled at last on the beautiful island of Hawaii, and for a while all seems to be well. But when Tycho spots an unexpected distress signal coming from the abandoned Moon, he and the others are immediately faced with the urgent task of rescuing whoever was left behind. But what started as a simple rescue mission quickly becomes a much more complex and dangerous expedition than anyone ever expected; one which will lead them to the far reaches of the solar system and the cold moon of Titan in search of a holy mountain that no human eye has ever seen.