NGC 5866 (also called the Spindle Galaxy or Messier 102) is a relatively bright lenticular or spiral galaxy in the constellation Draco. One of the most outstanding features of NGC 5866 is the extended dust disk, which is seen exactly edge-on. This dust disk is highly unusual for a lenticular galaxy. The dust in most lenticular galaxies is generally found only near the nucleus and generally follows the light profile of the galaxies' bulges. This dust disk may contain a ring-like structure, although the shape of this structure is difficult to determine given the edge-on orientation of the galaxy.It is also possible that the galaxy is a spiral galaxy that was misclassified as a lenticular galaxy because of its edge-on orientation, in which case the dust disk would not be too unusual.