The Dead Stars — Adam Christopher

When the test flight of the U-Star Manhattan - the first of a new class of starship - goes wrong, the seven-person crew find themselves shipwrecked, trapped in the interstitial nothingness that separates our universe from the next. But as the crew start to disappear one by one and the true purpose of their secret mission is uncovered, the survivors make a startling discovery about the eternal void they are lost in forever. They are not alone.