Dark Energy Spectroscopic Instrument

The Dark Energy Spectroscopic Instrument (DESI) will measure the effect of dark energy on the expansion of the universe. It will obtain optical spectra for tens of millions of galaxies and quasars, constructing a 3D map spanning the nearby universe to 11 billion light years.

The DESI Survey is being conducted on the Mayall 4-meter telescope at Kitt Peak National Observatory. DESI is supported by the Department of Energy Office of Science to perform this Stage IV dark energy measurement using baryon acoustic oscillations and other techniques that rely on spectroscopic measurements.

For more, see the DESI website, which includes the DESI team, sponsors,  and collaborating institutions pages.

Inside a large white rounded room, a black round tube (DESI) is attached to a larger structure. A set of orange stairs leads to DESI.
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Michael Levi, LBNL
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First light October 22, 2019
Mayall Telescope, Kitt Peak National Observatory, Tucson, Arizona