{"id":304809,"date":"2026-01-26T18:29:07","date_gmt":"2026-01-26T18:29:07","guid":{"rendered":"https:\/\/www.europesays.com\/ie\/304809\/"},"modified":"2026-01-26T18:29:07","modified_gmt":"2026-01-26T18:29:07","slug":"669-million-galaxies-6-years-of-data-scientists-finally-see-the-universes-dark-side","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/ie\/304809\/","title":{"rendered":"669 Million Galaxies, 6 Years of Data, Scientists Finally See the Universe\u2019s Dark Side"},"content":{"rendered":"

Researchers have assembled the most detailed view to date of how dark energy<\/strong> has shaped the cosmos, using six years of deep-sky observations. Drawing from the Dark Energy Survey (DES)<\/strong>, scientists traced the distribution of matter and the universe\u2019s expansion across billions of years, bringing them closer to understanding the force behind cosmic acceleration.<\/p>\n

The data, gathered by the Dark Energy Camera (DECam)<\/strong> on the V\u00edctor M. Blanco 4-meter Telescope<\/strong> in Chile, includes information from 669 million galaxies<\/strong> observed over 758 nights<\/strong> between 2013 and 2019. <\/p>\n

This force, which makes up roughly 68% of the universe<\/strong>, remains unexplained. With its multi-method strategy and massive data pool, the survey marks a significant step in unraveling one of astrophysics\u2019 most persistent mysteries.<\/p>\n

Combining Four Cosmic Tools<\/p>\n

To map the effects of dark energy, the DES team<\/a> used four key probes. The first is Type-Ia supernovae<\/a><\/strong>, bright stellar explosions used to measure cosmic distances. According to a study avaliable on arXiv<\/a><\/strong>, these objects were instrumental in the original discovery of dark energy and continue to serve as reliable indicators of expansion.<\/p>\n

Next, scientists used weak gravitational lensing<\/strong>, which occurs when massive objects distort the path of light from background galaxies. This subtle warping, according to DES researchers cited by NOIRLab\u2018s statement<\/a>, helps trace the distribution of dark matter and its interaction withdark energy<\/a>.<\/p>\n

They also examined galaxy clustering<\/a>, looking at how galaxies group across space and time, and incorporated baryon acoustic oscillations<\/strong>, density waves left over from the early universe. These oscillations serve as a standard ruler for measuring cosmic distances and provide additional context for how the universe evolved.<\/p>\n

\"AA stunning view of deep space captured by the Dark Energy Camera (DECam). Credit: NOIRLab<\/p>\n

Mismatch in Matter Distribution<\/strong><\/p>\n

The findings support the Lambda Cold Dark Matter (\u039bCDM) model<\/strong><\/a>, which assumes dark energy stays constant over time, and the wCDM<\/strong> model, which allows for some evolution. In both cases, the DES results aligned with predictions about how the universe expands.<\/p>\n

But when it came to how matter clusters<\/strong> in the current universe, the data told a different story. The degree of clustering observed didn\u2019t match what either model forecasted. This mismatch has become more pronounced with the latest data, hinting at a possible tension between theory and observation.<\/p>\n

\n

\u201cThis was something I would have only dared to dream about when DES started collecting data,\u201d said Yuanyuan Zhang<\/a>, a DES researcher at NOIRLab, in a statement \u201cAnd, now the dream has come true.\u201d<\/p>\n<\/blockquote>\n

Despite the models\u2019 broad consistency with the data, the matter clustering discrepancy remains unresolved and may point to new physics or gaps in current models.<\/p>\n

\"V\u00edctorThe V\u00edctor M. Blanco Telescope, home to the Dark Energy Camera used to map the universe. Credit: Noirlab<\/p>\n

Rubin\u2019s Turn to Map the Dark<\/strong><\/p>\n

The DES effort is set to merge with observations from the Vera C. Rubin Observatory<\/a>, which will conduct the Legacy Survey of Space and Time (LSST)<\/a><\/strong> over the next decade. This new survey aims to map 20 billion galaxies<\/strong>, far exceeding DES in scale. As stated by Chris Davis<\/a>, National Science Foundation Program Director:<\/p>\n

\n

\u201cRubin\u2019s unprecedented survey of the southern sky will enable new tests of gravity and shed light on dark energy.\u201d<\/p>\n<\/blockquote>\n

The combination of datasets from DES and Rubin is expected to offer clearer answers to the questions that current models leave open.<\/p>\n","protected":false},"excerpt":{"rendered":"Researchers have assembled the most detailed view to date of how dark energy has shaped the cosmos, using…\n","protected":false},"author":2,"featured_media":304810,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[271],"tags":[18,19,17,452,133],"class_list":{"0":"post-304809","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-physics","8":"tag-eire","9":"tag-ie","10":"tag-ireland","11":"tag-physics","12":"tag-science"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@ie\/115962823656729085","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts\/304809","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/comments?post=304809"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/posts\/304809\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/media\/304810"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/media?parent=304809"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/categories?post=304809"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/ie\/wp-json\/wp\/v2\/tags?post=304809"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}