No. 55: Jan-Feb 1988
Just a few years ago, most astronomers would have predicted that, as they examined larger and larger volumes of the universe, they would find more and more homogeneity. The Big Bang Theory predicts this; and it is seconded by the isotropy of the microwave background radiation. The mapping of the universe, however, has actually turned up all manner of galactic clusters, superclusters, and great skeins of superclusters strung across the heavens. Instead of a puree of matter, there is more and more structure the farther we peer into space.
R.B. Tully, at the University of Ha waii, now charts a billion-light-year structure that he calls the Pisces-Cetus complex. This aggregation of galaxies includes us (the Milky Way), our Local Supercluster, and many neighboring superclusters. In actuality, the PiscesCetus complex is not a continuous structure. Rather, it is defined by a plane -- one containing a host of superclusters as well as voids. The problem posed for theorists is that they can suggest no way in which such a far flung manifestation of order could have evolved in the time available since the Big Bang.
(Waldrop, M. Mitchell; "The Large-Scale Structure of the Universe Gets Larger-- Maybe," Science, 238:804, 1987.)