The Andromeda Galaxy was formed as the result of a massive collision involving two separate galaxies that occurred billions of years ago, an international team of researchers has discovered.

The most eminent astronomer who never came to popular attention was lost in the shadow of his countryman, Pierre-Simon Laplace The essayist and poet Ralph Waldo Emerson once remarked that an institution was the "lengthened shadow of one man," and that all of history could be resolved into the biography of "a few stout and earnest persons." Historians may choose to differ with Emerson, but when a giant is institutionalized in the form of an adjective-say, Newtonian or Darwinian-there is little doubt that the great one's shadow covers a lot of historical ground.