Number 57 (Story #1), November 27, 1991 by Phillip F. Schewe and Ben Stein A "ZEL'DOVICH PANCAKE," a massive protocluster of galaxies, may have been observed by radio astronomers at the Very Large Array in New Mexico. Named for the Russian astronomer Yakov B. Zel'dovich who pioneered the "top-down" theory of cosmology, these huge agglomerations of matter would have formed in the early universe from fluctuations in the density of matter; gravity would cause them to flatten into "pancakes." Later still these structures would fragment into galaxies. In contrast, the "bottom-down" theory holds that small structures such as galaxies come first followed by large structures such as galaxy clusters and superclusters. The new VLA observations have revealed a large radio-emitting object at a redshift of 3.4. The wavelength (21 cm) and narrow width of the emission line identify the source as being neutral hydrogen. The size, about 5 million light years across, and estimated mass, 3 x 1014 solar masses---suggest to Juan M. Uson and his colleagues Durgadas S. Bugri and Timothy J. Cornwell at the National Radio Astronomy Observatory that they are seeing evidence for a Zel'dovich Pancake. (Physical Review Letters, 9 December 1991.)