Jan. 8 — After scanning in depth about a quarter of the southern skies for six years and cataloguing hundreds of millions of distant galaxies, the Dark Energy Survey (DES) will finish taking data tomorrow, on January 9, 2019. The National Center for Supercomputing Applications (NCSA) at the University of Illinois will continue refining and serving this data for use by scientists into 2021.
The survey is an international collaboration that began mapping a 5,000-square-degree area of the sky on August 18, 2013, to search for evidence of dark energy, the mysterious force that is accelerating the expansion of the universe. Using the Dark Energy Camera, a 520-megapixel digital camera mounted on the Blanco 4-meter telescope at the Cerro Tololo Inter-American Observatory in Chile, scientists on DES took data for 758 nights over six years.
Over those nights, the survey generated 50 terabytes (that’s 50 trillion bytes) of data over its six observation seasons. That data is stored and analyzed at NCSA. Compute power for the project comes from NCSA’s NSF-funded Blue Waters supercomputer, the University of Illinois Campus Cluster, and Fermilab. “Even after observations end, NCSA will continue to support the science productivity of the collaboration by making refined data releases and serving the data well into the 2020s,” said Don Petravick, Senior Project Manager, Dark Energy Survey at NCSA. “We anticipate that this data will continue to enable breakthroughs in scientific applications and opportunities for discovery not only to astronomers but also data scientists.”
DES recorded data from nearly a billion galaxies that are billions of light-years from Earth. More than 400 scientists from over 25 institutions around the world have been involved in the project. This collaboration has already produced about 200 academic papers, with more to come.
The first step in that process, according to Fermilab’s Josh Frieman, former director of DES, is to find the signal in all the noise. “We’re trying to extract this signal of cosmology in a background of all sorts of non-cosmological stuff that gets imprinted on the data,” Frieman said. “It’s a massive ongoing effort from many different people around the world.”
According to DES Director Rich Kron, a Fermilab and University of Chicago scientist, those results and the scientists who made them possible are where much of the real accomplishment of DES lies.
“First generations of students and post-doctoral researchers on DES are now becoming faculty at research institutions and are involved in upcoming sky surveys,” Kron said. “The number of publications and people involved are a true testament to this experiment. Helping to launch so many careers has always been part of the plan, and it’s been very successful.”
DES scientists also spotted the first visible counterpart of gravitational waves ever detected, a collision of neutron stars that occurred 130 million years ago. DES was one of several sky surveys that detected this gravitational wave source, opening the door to a new kind of astronomy.
DES remains one of the most sensitive and comprehensive surveys of distant galaxies ever performed. The Dark Energy Camera is capable of seeing light from galaxies billions of light-years away, and capturing it in unprecedented quality. The Dark Energy Camera will remain mounted to the telescope at Cerro Tololo, and will continue to be a useful instrument for scientific collaborations around the world. With one era at an end, the next era of the Dark Energy Survey is just beginning.
The DES collaboration continues to release scientific results from their storehouse of data. Highlights from the previous years include:
- The most precise measurement of dark matter structure in the universe, and comparing it with cosmic microwave background results to see the evolution of the cosmos
- The discovery of many more dwarf satellite galaxies orbiting our Milky Way than originally thought
- The creation of the most accurate dark matter map of the universe
- The spotting of the most distant supernova ever detected
- The public release of the survey’s first three years of data, enabling astronomers around the world to make similar discoveries
The Dark Energy Survey (DES) is a collaboration of more than 400 scientists from 26 institutions in seven countries. Funding for the DES Projects has been provided by the U.S. Department of Energy Office of Science, U.S. National Science Foundation, Ministry of Science and Education of Spain, Science and Technology Facilities Council of the United Kingdom, Higher Education Funding Council for England, ETH Zurich for Switzerland, National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign, Kavli Institute of Cosmological Physics at the University of Chicago, Center for Cosmology and AstroParticle Physics at Ohio State University, Mitchell Institute for Fundamental Physics and Astronomy at Texas A&M University, Financiadora de Estudos e Projetos, Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro, Conselho Nacional de Desenvolvimento Científico e Tecnológico and Ministério da Ciência e Tecnologia, Deutsche Forschungsgemeinschaft, and the collaborating institutions in the Dark Energy Survey, the list of which can be found at www.darkenergysurvey.org/collaboration.
For more than 30 years the National Center for Supercomputing Applications (NCSA) at the University of Illinois has been discovering solutions to grand challenges for the benefit of science and society that once seemed unimaginable. NCSA helps collaborators push beyond their limitations to make groundbreaking discoveries with the most advanced digital resources and world-class staff. For more information, please visit www.ncsa.illinois.edu.
About the Cerro Tololo Inter-American Observatory
The Cerro Tololo Inter-American Observatory, National Optical Astronomy Observatory, is operated by the Association of Universities for Research in Astronomy (AURA) under a cooperative agreement with the National Science Foundation.
Fermilab is America’s premier national laboratory for particle physics and accelerator research. A U.S. Department of Energy Office of Science laboratory, Fermilab is located near Chicago, Illinois, and operated under contract by the Fermi Research Alliance LLC, a joint partnership between the University of Chicago and the Universities Research Association, Inc. Visit Fermilab’s website at www.fnal.gov and follow us on Twitter at @Fermilab.
About the DOE Office of Science
The DOE Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.
About the NSF
The National Science Foundation (NSF) is an independent federal agency that supports fundamental research and education across all fields of science and engineering. In fiscal year (FY) 2017, its budget is $7.5 billion. NSF funds reach all 50 states through grants to nearly 2,000 colleges, universities and other institutions. Each year, NSF receives more than 48,000 competitive proposals for funding and makes about 12,000 new funding awards. For more information, visit www.nsf.gov.