Yesterday's Spelljammer

From the introduction: The adventure begins with the PC's ship approaching a major world like Toril, Krynn, Oerth, or some other world that plays a prominent role in your campaign. All appears to be well, until a huge multi-colored field appears above the southern hemisphere of the planet, and the great Spelljammer itself appears out of nowhere! This will certainly catch the PC's attention, if not because of the jammer, then the field from which it came. User summary: This scenario is quite brief.