{"id":504704,"date":"2026-07-01T15:42:12","date_gmt":"2026-07-01T15:42:12","guid":{"rendered":"https:\/\/www.newsbeep.com\/nz\/504704\/"},"modified":"2026-07-01T15:42:12","modified_gmt":"2026-07-01T15:42:12","slug":"hubble-detects-ultraviolet-light-from-tiny-starburst-galaxy-in-early-universe","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/nz\/504704\/","title":{"rendered":"Hubble Detects Ultraviolet Light from Tiny Starburst Galaxy in Early Universe"},"content":{"rendered":"

Just 1.4 billion years after the Big Bang, MXDFz4.4 \u2014 a galaxy 100 times smaller than the Milky Way \u2014 was blasting ionizing light through the neutral hydrogen that once shrouded everything, giving astronomers their closest-ever look at cosmic reionization in action.<\/p>\n

\"This<\/a><\/p>\n

This illustration portrays galaxy MXDFz4.4 when it existed 1.4 billion years after the Big Bang. Image credit: NASA \/ ESA \/ Leah Hustak, STScI.<\/p>\n

MXDFz4.4 existed at the end of the Epoch of Reionization, a transformative period in our Universe.<\/p>\n

During roughly the first billion years after the Big Bang, the gas between stars and galaxies was opaque to energetic ultraviolet light.<\/p>\n

As time wore on, gas everywhere became transparent or ionized. The changeover was not like an on\/off switch, but likely took hundreds of millions of years.<\/p>\n

\u201cObserving a galaxy like this was thought to be impossible,\u201d said Dr. Ilias Goovaerts, a postdoctoral fellow at the Space Telescope Science Institute.<\/p>\n

\u201cResearchers expected the \u2018fog\u2019 or neutral hydrogen that filled the early Universe would be too thick and obscure our view of its ionizing light.\u201d<\/p>\n

\u201cHubble not only spotted that light, but it also helped reveal incredible details about the galaxy\u2019s characteristics.\u201d<\/p>\n

\"Detailed<\/a><\/p>\n

Detailed visible-light images from Hubble reveal that several bursts of younger stars cleared the space in and around MXDFz4.4. Image credit: NASA \/ ESA \/ CSA \/ STScI \/ Ilias Goovaerts, STScI \/ Marc Rafelski, STScI & JHU \/ Anton Koekemoer, STScI \/ Alyssa Pagan, STScI.<\/p>\n

\u201cAstronomers have found many galaxies that existed at this point in the history of the Universe, but we haven\u2019t detected ionizing photons from any of them, making MXDFz4.4 one of a kind,\u201d said Dr. Marc Rafelski, also from the Space Telescope Science Institute.<\/p>\n

Hubble\u2019s long exposures, pulled from several existing surveys, revealed that MXDFz4.4\u2019s young, massive stars are the source of the ultraviolet light, which cleared the surrounding space.<\/p>\n

These stars formed in bursts within the last few million years of the galaxy\u2019s existence and are crammed together.<\/p>\n

Amplifying this crowding effect, MXDFz4.4 is about 100 times smaller than our Milky Way Galaxy, but is forming stars 10 times faster.<\/p>\n

\u201cA lot of young, hot, massive stars in a small space do a better job of blasting through opaque gas,\u201d Dr. Goovaerts said.<\/p>\n

The team\u2019s paper<\/a> was published on June 23, 2026 in the Astrophysical Journal.<\/p>\n

_____<\/p>\n

Ilias Goovaerts et al. 2026. MXDFz4.4: A LyC Emitter 250 Myr after the Epoch of Reionization and a First Test of Ly\u03b1 Morphology as a Tracer of LyC Escape at High Redshift. ApJ 1005, 34; doi: 10.3847\/1538-4357\/ae75b0<\/p>\n","protected":false},"excerpt":{"rendered":"Just 1.4 billion years after the Big Bang, MXDFz4.4 \u2014 a galaxy 100 times smaller than the Milky…\n","protected":false},"author":2,"featured_media":504705,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[2904,114024,1022,5434,15110,41227,251766,3323,111,139,69,147,6988,189671,23272,60952],"class_list":["post-504704","post","type-post","status-publish","format-standard","has-post-thumbnail","category-science","tag-early-universe","tag-epoch-of-reionization","tag-esa","tag-galaxy","tag-hubble","tag-hydrogen","tag-mxdfz4-4","tag-nasa","tag-new-zealand","tag-newzealand","tag-nz","tag-science","tag-star-formation","tag-starburst-galaxy","tag-universe","tag-uv"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/504704","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/comments?post=504704"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/posts\/504704\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media\/504705"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/media?parent=504704"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/categories?post=504704"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/nz\/wp-json\/wp\/v2\/tags?post=504704"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}