The Dark Energy Survey (DES) is an international, collaborative effort which has mapped over 300 million galaxies, detected thousands of supernovae, and continues to find patterns of cosmic structure that help to reveal the nature of the mysterious dark energy that is accelerating the expansion of our Universe. DES began searching the Southern skies on August 31, 2013 and ended its observations on January 9, 2019
DES is designed to probe the origin of the accelerating universe and help uncover the nature of dark energy by measuring the 14-billion-year history of cosmic expansion with high precision. More than 400 scientists from over 26 institutions in multiple countries are working on the project. The collaboration built and used an extremely sensitive 570-Megapixel digital camera, DECam, mounted on the Blanco 4-meter telescope at Cerro Tololo Inter-American Observatory, high in the Chilean Andes, to carry out the project.
The DES collaboration used over 800 nights of observation to carry out a deep, wide-area survey to record information from 300 million galaxies that are billions of light-years from Earth. The survey imaged 5000 square degrees of the southern sky, with 3400 sq-degrees overlapping the Sunyaev-Zel'dovich CMB surveys conducted by SPT, in five optical filters to obtain detailed information about each galaxy. A fraction of the survey time was used to observe smaller patches of sky roughly once a week to discover and study thousands of supernovae and other astrophysical transients.
With observations now complete, DES collaborators are now analyzing the vast amounts of data contained within the data set. A full range of results based upon the first year’s data has been released and the data from the following years is now being carefully investigated to find clues to the nature of dark energy.