{"id":8476,"date":"2026-02-18T15:32:02","date_gmt":"2026-02-18T15:32:02","guid":{"rendered":"https:\/\/godshand.link\/ground_post\/nasas-hubble-identifies-one-of-darkest-known-galaxies\/"},"modified":"2026-02-18T15:32:02","modified_gmt":"2026-02-18T15:32:02","slug":"nasas-hubble-identifies-one-of-darkest-known-galaxies","status":"publish","type":"ground_post","link":"https:\/\/godshand.link\/en_gb\/ground_post\/nasas-hubble-identifies-one-of-darkest-known-galaxies\/","title":{"rendered":"NASA\u2019s Hubble Identifies One of Darkest Known Galaxies"},"content":{"rendered":"<p><br \/>\n<\/p>\n<div xmlns:default=\"http:\/\/www.w3.org\/2000\/svg\">\n<div class=\"stma-image-wrapper bg-carbon-black nasa-block-align-wide\">\n<div class=\"image-container\" aria-label=\"Interactive image\"><img width=\"3219\" height=\"1330\" src=\"https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/missions\/hubble\/releases\/2026\/02\/STScI-01K7PSFCSX5NBNBT6778SKHZ2D.jpg?w=3219&amp;h=1330&amp;fit=clip&amp;crop=faces%2Cfocalpoint\" class=\"attachment-card-md size-card-md\" alt=\"At left, a field of space with a dozen white foreground stars and a number of small, yellow background galaxies. An unremarkable area at center is outlined with a dashed red circle surrounded by a white box. Lines extend from the box to a pullout at right containing faint, grainy white light surrounded by a red circle labeled \u201cCandidate dark galaxy \u2013 diffuse emission.\u201d Four white dots are circled in blue and labeled globular clusters.\" style=\"transform: scale(1); transform-origin: 50% 50%; object-position: 50% 50%; object-fit: cover;\" block_context=\"nasa-block\" loading=\"lazy\" decoding=\"async\" srcset=\"https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/missions\/hubble\/releases\/2026\/02\/STScI-01K7PSFCSX5NBNBT6778SKHZ2D.jpg?w=3219&amp;h=1330&amp;fit=crop&amp;crop=faces%2Cfocalpoint 3219w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/missions\/hubble\/releases\/2026\/02\/STScI-01K7PSFCSX5NBNBT6778SKHZ2D.jpg?w=300&amp;h=124&amp;fit=crop&amp;crop=faces%2Cfocalpoint 300w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/missions\/hubble\/releases\/2026\/02\/STScI-01K7PSFCSX5NBNBT6778SKHZ2D.jpg?w=768&amp;h=317&amp;fit=crop&amp;crop=faces%2Cfocalpoint 768w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/missions\/hubble\/releases\/2026\/02\/STScI-01K7PSFCSX5NBNBT6778SKHZ2D.jpg?w=1024&amp;h=423&amp;fit=crop&amp;crop=faces%2Cfocalpoint 1024w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/missions\/hubble\/releases\/2026\/02\/STScI-01K7PSFCSX5NBNBT6778SKHZ2D.jpg?w=1536&amp;h=635&amp;fit=crop&amp;crop=faces%2Cfocalpoint 1536w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/missions\/hubble\/releases\/2026\/02\/STScI-01K7PSFCSX5NBNBT6778SKHZ2D.jpg?w=2048&amp;h=846&amp;fit=crop&amp;crop=faces%2Cfocalpoint 2048w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/missions\/hubble\/releases\/2026\/02\/STScI-01K7PSFCSX5NBNBT6778SKHZ2D.jpg?w=400&amp;h=165&amp;fit=crop&amp;crop=faces%2Cfocalpoint 400w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/missions\/hubble\/releases\/2026\/02\/STScI-01K7PSFCSX5NBNBT6778SKHZ2D.jpg?w=600&amp;h=248&amp;fit=crop&amp;crop=faces%2Cfocalpoint 600w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/missions\/hubble\/releases\/2026\/02\/STScI-01K7PSFCSX5NBNBT6778SKHZ2D.jpg?w=900&amp;h=372&amp;fit=crop&amp;crop=faces%2Cfocalpoint 900w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/missions\/hubble\/releases\/2026\/02\/STScI-01K7PSFCSX5NBNBT6778SKHZ2D.jpg?w=1200&amp;h=496&amp;fit=crop&amp;crop=faces%2Cfocalpoint 1200w, https:\/\/assets.science.nasa.gov\/dynamicimage\/assets\/science\/missions\/hubble\/releases\/2026\/02\/STScI-01K7PSFCSX5NBNBT6778SKHZ2D.jpg?w=2000&amp;h=826&amp;fit=crop&amp;crop=faces%2Cfocalpoint 2000w\" sizes=\"auto, (max-width: 3219px) 100vw, 3219px\"\/><\/div>\n<\/div><figcaption class=\"nasa-block-align-wide hds-caption padding-y-2\">\n<p>The low-surface-brightness galaxy CDG-2, within the dashed red circle at right, is dominated by dark matter and contains only a sparse scattering of stars. The full image from NASA\u2019s Hubble Space Telescope is at left.<\/p>\n<p>NASA, ESA, Dayi Li (UToronto); Image Processing: Joseph DePasquale (STScI)<\/p>\n<\/figcaption><p>In the vast tapestry of the universe, most galaxies shine brightly across cosmic time and space. Yet a rare class of galaxies remains nearly invisible \u2014 low-surface-brightness galaxies dominated by dark matter and containing only a sparse scattering of faint stars.<\/p>\n<p>One such elusive object, dubbed CDG-2, may be among the most heavily dark matter-dominated galaxies ever discovered. (Dark matter is an invisible form of matter that does not reflect, emit, or absorb light.) The science paper detailing this finding was published in <a target=\"_blank\" href=\"https:\/\/iopscience.iop.org\/article\/10.3847\/2041-8213\/adddab\/meta\">The Astrophysical Journal Letters<\/a>.<\/p>\n<p>Detecting such faint galaxies is extraordinarily difficult. Using advanced statistical techniques, David Li of the University of Toronto, Canada, and his team identified 10 previously confirmed low-surface-brightness galaxies and two additional dark galaxy candidates by searching for tight groupings of globular clusters \u2014 compact, spherical star groups typically found orbiting normal galaxies. These clusters can signal the presence of a faint, hidden stellar population.<\/p>\n<p>To confirm one of the dark galaxy candidates, astronomers employed a trio of observatories: NASA\u2019s <a target=\"_blank\" href=\"https:\/\/science.nasa.gov\/mission\/hubble\/\">Hubble Space Telescope<\/a>, ESA\u2019s (European Space Agency) <a target=\"_blank\" href=\"https:\/\/www.esa.int\/Science_Exploration\/Space_Science\/Euclid\" rel=\"noreferrer noopener nofollow\">Euclid<\/a> space observatory, and the ground-based <a target=\"_blank\" href=\"https:\/\/subarutelescope.org\/en\/\" rel=\"noreferrer noopener nofollow\">Subaru Telescope<\/a> in Hawaii. Hubble\u2019s high-resolution imaging revealed a close collection of four globular clusters in the Perseus galaxy cluster, 300 million light-years away. Follow-up studies using Hubble, Euclid, and Subaru data then revealed a faint, diffuse glow surrounding the star clusters \u2014 strong evidence of an underlying galaxy.<\/p>\n<p>\u201cThis is the first galaxy detected solely through its globular cluster population,\u201d said Li. \u201cUnder conservative assumptions, the four clusters represent the entire globular cluster population of CDG-2.\u201d<\/p>\n<figure class=\"wp-block-embed alignwide is-type-video is-provider-youtube wp-block-embed-youtube\">\n<p>\n<iframe loading=\"lazy\" title=\"&quot;Dark Galaxy&quot; Identified by Hubble\" width=\"1170\" height=\"658\" src=\"https:\/\/www.youtube.com\/embed\/EnzPNWDlSeM?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" allowfullscreen><\/iframe>\n<\/p><figcaption class=\"wp-element-caption\">NASA&#8217;s Goddard Space Flight Center; Lead Producer: Paul Morris<\/figcaption><\/figure>\n<p>Preliminary analysis suggests CDG-2 has the luminosity of roughly 6 million Sun-like stars, with the globular clusters accounting for 16% of its visible content. Remarkably, 99% of its mass, which includes both visible matter and dark matter, appears to be dark matter. Much of its normal matter to enable star formation \u2014 primarily hydrogen gas \u2014 was likely stripped away by gravitational interactions with other galaxies inside the Perseus cluster.<\/p>\n<p>Globular clusters possess immense stellar density and are gravitationally tightly bound. This makes the clusters more resistant to gravitational tidal disruption, and therefore reliable tracers of such ghostly galaxies.<\/p>\n<p>As sky surveys expand with missions like Euclid, NASA\u2019s upcoming <a target=\"_blank\" href=\"https:\/\/science.nasa.gov\/mission\/roman-space-telescope\/\">Nancy Grace Roman Space Telescope<\/a>, and the <a target=\"_blank\" href=\"https:\/\/rubinobservatory.org\/\" rel=\"noreferrer noopener nofollow\">Vera C. Rubin Observatory<\/a>, astronomers are increasingly turning to machine learning and statistical methods to sift through vast datasets.<\/p>\n<p><em>The Hubble Space Telescope has been operating for more than three decades and continues to make ground-breaking discoveries that shape our fundamental understanding of the universe. Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA\u2019s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope and mission operations. Lockheed Martin Space, based in Denver, also supports mission operations at Goddard. The Space Telescope Science Institute in Baltimore, which is operated by the Association of Universities for Research in Astronomy, conducts Hubble science operations for NASA.<\/em><\/p>\n<\/div>\n<p><br \/>\n<br \/><a href=\"https:\/\/science.nasa.gov\/missions\/hubble\/nasas-hubble-identifies-one-of-darkest-known-galaxies\/?rand=6321\" target=\"_blank\">Source link <\/a><\/p>","protected":false},"excerpt":{"rendered":"<p>The low-surface-brightness galaxy CDG-2, within the dashed red circle at right, is dominated by dark matter and contains only a sparse scattering of stars. The full image from NASA\u2019s Hubble Space Telescope is at left. NASA, ESA, Dayi Li (UToronto); Image Processing: Joseph DePasquale (STScI) In the vast tapestry of the universe, most galaxies shine brightly across cosmic time and&hellip;<\/p>","protected":false},"author":1,"featured_media":8477,"parent":0,"menu_order":0,"comment_status":"open","ping_status":"open","template":"","format":"standard","meta":{"give_campaign_id":0,"footnotes":""},"tags":[1935,407,337,1934,331],"ground_category":[137,138],"class_list":["post-8476","ground_post","type-ground_post","status-publish","format-standard","has-post-thumbnail","hentry","tag-darkest","tag-galaxies","tag-hubble","tag-identifies","tag-nasas","ground_category-1-grounds-science","ground_category-1-1-discover-universe"],"fifu_image_url":"https:\/\/assets.science.nasa.gov\/content\/dam\/science\/missions\/hubble\/releases\/2026\/02\/STScI-01K7PSFCSX5NBNBT6778SKHZ2D.jpg\/jcr:content\/renditions\/cq5dam.web.1280.1280.jpeg","_links":{"self":[{"href":"https:\/\/godshand.link\/en_gb\/wp-json\/wp\/v2\/ground_post\/8476","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/godshand.link\/en_gb\/wp-json\/wp\/v2\/ground_post"}],"about":[{"href":"https:\/\/godshand.link\/en_gb\/wp-json\/wp\/v2\/types\/ground_post"}],"author":[{"embeddable":true,"href":"https:\/\/godshand.link\/en_gb\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/godshand.link\/en_gb\/wp-json\/wp\/v2\/comments?post=8476"}],"version-history":[{"count":0,"href":"https:\/\/godshand.link\/en_gb\/wp-json\/wp\/v2\/ground_post\/8476\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/godshand.link\/en_gb\/wp-json\/wp\/v2\/media\/8477"}],"wp:attachment":[{"href":"https:\/\/godshand.link\/en_gb\/wp-json\/wp\/v2\/media?parent=8476"}],"wp:term":[{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/godshand.link\/en_gb\/wp-json\/wp\/v2\/tags?post=8476"},{"taxonomy":"ground_category","embeddable":true,"href":"https:\/\/godshand.link\/en_gb\/wp-json\/wp\/v2\/ground_category?post=8476"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}