Dark Energy Spectroscopy Releases First Data
A team of more than 1,000 scientists from all over the world released this week the first set of data collected by the Dark Energy Spectroscopy instrument (DESI), a new telescope that cosmologists are hoping will answer questions about the nature of dark energies and the evolution the Universe [1-3]. Michael Levi, a cosmologist and director of the DESI Collaboration at the Lawrence Berkeley National Laboratory in California, says that the telescope is working better than anyone could have imagined. \”We’re ready for everyone to look at [the initial] data release, and see what they can make of it.\”
The five-year DESI survey aims to map the Universe in greater detail and at a deeper time scale than any other telescope. (See Feature: A New Era in Dark Energy Cosmology). \”We want to go way beyond what was done before and really be able to see the evolution of dark energy over the history of the Universe,\” says Nathalie Palanque-Delabrouille, a cosmologist at LBNL and one of the spokespeople for the DESI Collaboration. The survey will pinpoint the locations for over 40 million galaxies to see this evolution. Robotic technology is used to automatically change the positions of light-collecting fibres in order to retrieve spectroscopic data from bright spots in a sky. The spectral measurements give us information about what the object is, and how quickly it moves away from us. This is necessary to estimate its distance.
Levi says that because the robotic technology to target objects was never tested before, it wasn’t always obvious whether DESI would work as expected. Levi and his team have been surprised at how well the machine works. He says that \”DESI preserved every photon the Universe gave us.\”
Source:
https://physics.aps.org/articles/v16/106
