These were built as an instrument for cosmology and are also known as the Sunyaev-Zel'dovich Array (SZA), a project led by John Carlstrom at the University of Chicago. The SZA spent three years on the valley floor at the Owens Valley Radio Observatory observing the cosmic microwave background (CMB) and galaxy clusters. In the summer of 2008 it was moved up to Cedar Flat.