What do apartment buildings and distant galaxies have in common?

Observing older, massive galaxies in the “Redshift Desert” is similar to trying to determine the number of residents in an apartment building by counting the number of lit windows. In past surveys of this period of our Universe, mainly the brighter galaxies where stars are forming were bright enough to be studied. Prior to the Gemini Deep Deep Survey (GDDS), the more massive, older and fainter galaxies were not well represented in surveys of this epoch in the Universe––like the dark windows in the buildings above. The Gemini spectra from the GDDS allows us to study these dimmer galaxies and understand their properties such as mass, age and heavy element abundances.