Astrophysicists Map Dark Matter and Dark Energy in Universe

Astrophysicists at the University of Chicago have made significant advancements in mapping dark matter and dark energy by studying warped galaxies. Between 2013 and 2019, the Dark Energy Survey gathered observations with the Dark Energy Camera on the 4-meter Blanco Telescope at the Cerro Tololo Inter-American Observatory in Chile.

This survey measured and calibrated the shapes of more than 150 million galaxies across 5,000 square degrees of the sky. The team, led by Chihway Chang, utilized weak gravitational lensing to understand how mass is distributed throughout the universe, including both ordinary and dark matter.

The DECADE project, which expanded the data set by including thousands of square degrees beyond the original survey area, nearly doubled the number of galaxies with measured shapes. The analysis involved measuring galaxy distances through redshift, which indicates how quickly galaxies are moving away from Earth.

The results show that cosmic structure growth aligns with predictions of the Lambda-CDM model, a widely accepted cosmological framework. This finding addresses previous discrepancies between early universe observations inferred from cosmic microwave background radiation and recent galaxy surveys.

The combined analysis of DECADE and DES data covers about one-third of the sky and includes 270 million galaxies, marking one of the most comprehensive galaxy lensing studies to date. The final catalog was released to the scientific community this fall, enabling further research on various cosmological aspects.

The collaboration involved scientists from UChicago, Fermilab, and other institutions worldwide, showcasing a successful integration of diverse expertise in astrophysics.