Abaddon's Gate is the third book in the New York times bestselling expanse series. For generations, the solar system - mars, the moon, the asteroid belt - Was Humanity's great frontier. Until now. The alien artefact work...Abaddon's Gate is the third book in the New York times bestselling expanse series. For generations, the solar system - mars, the moon, the asteroid belt - Was Humanity's great frontier. Until now. The alien artefact working through its program under the clouds of venus has emerged to build a massive structure outside the orbit of uranus: a gate that leads into a starless dark.