IS THE UNIVERSE CRYSTALLINE? As astronomers measure redshifts for additional galaxy superclusters, the three-dimensional architecture of the universe becomes more evident. New redshift surveys, reaching ever further into space, are benefiting from fiber optics and increasing automation. A fresh analysis of current redshift catalogs offers some evidence for a periodic arrangement of superclusters, separated by voids, on a scale of 120 megaparsecs (about 390 million light years). Great walls of galaxies on this scale have been discerned before but the apparent periodicity is new. The researchers suggest that a new theory might be needed to explain the sort of immense 3D- chessboard structure they seem to be finding in the data. (J. Einasto et al., Nature 9 January 1997.)