Mapping the Location of Millions of Galaxies

Image of John Huchra courtesy of John Huchra.

Once Edwin Hubble showed that the Milky Way was not the only galaxy, astronomers began to take finer and finer images of distant galaxies, and it soon became evident that galaxies came in clusters.  Our own cluster, called the “Local Group” has about 20 galaxies. Some clusters have more than 1,000 galaxies.  But are there clusters of clusters of galaxies?

 

Uncovering the large scale structure of galaxies in the universe required not only looking at images, but finding the distance to each galaxy, in order to create a three-dimensional map, showing how galaxies are distributed in the universe.  John Huchra and Margaret Geller became the leaders in this effort.

 

The equipment to measure the distances to many galaxies quickly first became available in the mid 1970s.  And these first surveys suggested large scale structures.