A first light image from the DESI instrument showing spectra collected from the Triangulum galaxy (M-33) by one of 5,000 fiber optic detectors. The instrument’s field of view is nearly 40 times the size of the moon. Image: DESI Collaboration
Astronomers have collected a “first light” image from the 4-metre Mayall telescope and the 11-ton Dark Energy Spectroscopic Instrument, or DESI, equipped with 5,000 fiber optic “eyes” feeding a bank of 10 spectrographs. The system is capable of breaking down the light from 5,000 galaxies every 20 minutes to determine their distances and velocities.
The goal of the project, starting early next year, is to pin down the positions and distances to 35 million galaxies spread across one third of the sky to glean clues about the nature of the mysterious “dark energy” causing the expansion of the universe to accelerate.
With a field of view of 8 square degrees – about 40 times the area of the full moon – DESI can assess more than 100,000 galaxies in a single night.
“After a decade in planning and R&D, installation and assembly, we are delighted that DESI can soon begin its quest to unravel the mystery of dark energy,” said ...