dark energy

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The Dark Energy Survey collaboration has created the largest ever maps of the distribution and shapes of galaxies, tracing both ordinary and dark matter in the universe out to a distance of over 7 billion light years. The analysis, which includes the first three years of data from the survey, is consistent with predictions from the current best model of the universe, the standard cosmological model. Nevertheless, there remain hints from DES and other experiments that matter in the current universe is a few percent less clumpy than predicted.

From the University of Chicago, May 21, 2021: Long-time University of Chicago professor of astronomy and astrophysics, Richard Kron created the Sloan Digital Sky Survey which set the stage for the Dark Energy Survey. Although he is retiring this year after 40 years of mapping the universe, he plans on staying on as director of the Dark Energy Survey.

A tessellated image of a white cap with a blue dot on the right edge, with shadow surrounding. This image is tessellated many times. A single cap, center right, is different: It has a white dot with a white concentric circle around it on top. No blue.

DESI will capture and study the light from tens of millions of galaxies and other distant objects to better understand our universe and the properties of dark energy. The formal start of DESI’s five-year survey follows a four-month trial run of its custom instrumentation that captured 4-million spectra of galaxies — more than the combined output of all previous spectroscopic surveys. Fermilab has contributed multiple components to the international collaboration led by Berkeley Lab.

From Jumbo News, March 31, 2021: Fermilab’s Josh Frieman, Tom Diehl, Antonella Palmese, and Rich Kron as part of the Dark Energy Survey collaboration, have completed scanning a quarter of the southern skies for six years and cataloguing hundreds of millions of distant galaxies.

From Super Interessante, Jan. 31, 2021: A team of researchers from Fermilab and the National Observatory in Brazil used the light of solitary stars to calculate the mass of some of the largest structures in the cosmos — galaxy clusters. In addition to taking the most detailed measurement ever published of intracluster light, the team’s new method of measurement can help further investigate dark matter.