The orbits of the Magellanic Clouds about the Milky Way Galaxy have apparently been determined, and the two dwarf irregular galaxies are now about as close as they will get to the MW in their 2.2 billion year orbit. See p. 42 of "Our Growing, Breathing Galaxy" by Wakker and Richter, Scientific American, January, 2004, pp. 38-47. If the orbit of the Magellanic Clouds can be determined with modern observing technology, what of the Andromeda Galaxy? Is it known when and how close Andromeda and the MW will meet at their closest approach?