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In 1977, the Smithsonian-Harvard Center for Astrophysics (CfA) began the first large-scale mapping of the superstructure of the universe. Led by Marc Davis, John Huchra, Dave Latham and John Tonry, this project measured the red shifts (and therefore, their radial velocity from our own galaxy) of a great number of galaxies, creating the first crude look at the overall structure of the universe.

A second effort (CfA2), begun in 1985 by Huchra and Margaret Gellar, continued the original project on a much broader scale, measuring and cataloging the red shifts of nearly 18,000 galaxies by 1995, and work continues to this day. New theoretical work by Gellar allowed for the creation of stunning 3D maps of the surrounding universe to a distance of nearly 1 billion light-years.

The CfA survey is quite possibly one of the most important projects in cosmology, as it revealed that the universe had a structure dominated by tremendous voids, and most of the galaxies were concentrated in gigantic sheets and filaments surrounding these voids. Early results revealed now famous structures known as the Stickman (the Coma Cluster, located in the constellation Coma Bernices) and the Great Wall, a thin sheet of galaxies that, at 600 million light-years wide, 250 million light-years high, a 30 million light-years deep, comprise the largest known structure in the universe.

This "soapsud" structure baffled cosmologists, who, in 1985, were still looking at a relatively uniform cosmic background radiation pattern, and expected to see an approximately even distribution of galaxies. Cosmologists today are still at something of a loss to describe the exact mechanism, but the consensus is that quantum fluctuations shortly after the Big Bang triggered uneven inflation, causing large areas to balloon up and triggering galactic formation along the edges.

Check out John Huchra's homepage at http://cfa-www.harvard.edu/~huchra/

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