The Large and Small Magellanic Clouds set the Milky Way's dark-matter halo in motion as they orbit. This, in turn, excites oscillations in the Milky Way's gaseous disk. This is a still from a movie of how the Magellanic Clouds produce our galaxy's warp. The Milky Way is at center, and the position of the Sun is about half way out in the picture of the galaxy along the line marked X. The crosshatched area represents the warped hydrogen layer. The looping line represents the 1.5-billion-year orbit of the Magellanic Clouds (shown as a yellow bead at the satellites' present position). Click on the link below to see this animation.
Courtesy Leo Blitz