The Orb in the Sky, more commonly known as "the comet" or "the fourth moon", is a strange celestial body that first appeared in The Brightest Night as Sunny and Clay flew over the MudWing army encampment. Sunny describes it as the appearance of a fourth moon, making another brightest night, "even though there should not have been another for ninety-four more years." She also sees it to be an omen with spiritual meaning.