The Dark Tower in Scorpius . ... Credit Copyright: Thomas V. Davis ( tvdavisastropix.com ) Explanation: In silhouette against a crowded star field toward the constellation Scorpius , this dusty cosmic cloud evokes for some the image of an ominous dark tower . In fact, clumps of dust and molecular gas collapsing to form stars may well lurk within the dark nebula, a structure that spans almost 40 light-years across the gorgeous telescopic view . ... NASA Official: Jay Norris. ...