I picked up the quest "Tracing the Stars I" from Mara while on my Warlock. Later, I did the Bay of Drowned Wishes Legend Lost Sector on my Hunter, who did not have the "Tracing the Stars" quest in his inventory. The "Drowned Bay Alcove" Atlas Skew appeared and I picked it up, not realizing what it was. Now, the Atlas Skew no longer appears, and the quest shows that I do not have it (no matter which character - I've tried all three).