A five-year quest to map the universe and unravel the mysteries of “dark energy” has begun and researchers at the University of Michigan in Ann Arbor were instrumental in the project’s development.
The Dark Energy Spectroscopic Instrument (DESI) at Kitt Peak National Observatory near Tucson, Ariz., is an international collaboration under the aegis of the U.S. Department of Energy’s Lawrence Berkeley National Laboratory with primary funding from DOE’s Office of Science.
The project aims to create a 3-D map of the universe, unraveling the mysterious dark energy. To complete its quest, the instrument will capture and study the light from tens of millions of galaxies and other distant objects in the universe.
To do this, the instrument will aim its robotic array of 5,000 fiber-optic “eyes” at the night sky to capture the first images showing its unique view of galaxy light. The robotic eyes were assembled by U-M students and technicians, under the leadership of physicist Gregory Tarlé. The team delivered a total of 7,300 robotic fiber positioners, including spares.
By gathering light from some 30 million galaxies, project scientists say DESI will help them construct a 3-D map of the universe with unprecedented detail. The data will help them better understand the repulsive force associated with dark energy that drives the acceleration of the expansion of the universe across vast cosmic distances.
“DESI is the most advanced cosmic cartography experiment ever attempted,” says Tarlé, U-M professor of physics and chair of the DESI Institutional Board. “By observing the spectrum of tens of millions of galaxies and quasars, 10 times more than any previous experiment, DESI will construct a detailed three-dimensional map of our universe.
“With this map, we will be able to trace the impact of the mysterious dark energy through 11 billion years of cosmic time and attempt to understand its nature. This is such an exciting time, marking the culmination of almost a decade of work by dozens of institutions from all over the world to build DESI, carry out the targeting surveys and make it work on the sky.”