{"id":133666,"date":"2026-02-12T14:00:28","date_gmt":"2026-02-12T19:00:28","guid":{"rendered":"https:\/\/www.simonsfoundation.org\/?p=133666"},"modified":"2026-03-05T16:29:05","modified_gmt":"2026-03-05T21:29:05","slug":"caught-in-the-act-astronomers-watch-a-vanishing-star-turn-into-a-black-hole","status":"publish","type":"post","link":"https:\/\/www.simonsfoundation.org\/2026\/02\/12\/caught-in-the-act-astronomers-watch-a-vanishing-star-turn-into-a-black-hole\/","title":{"rendered":"Caught in the Act: Astronomers Watch a Vanishing Star Turn Into a Black Hole"},"content":{"rendered":"","protected":false},"excerpt":{"rendered":"","protected":false},"author":7,"featured_media":133737,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_relevanssi_hide_post":"","_relevanssi_hide_content":"","_relevanssi_pin_for_all":"","_relevanssi_pin_keywords":"","_relevanssi_unpin_keywords":"","_relevanssi_related_keywords":"","_relevanssi_related_include_ids":"","_relevanssi_related_exclude_ids":"","_relevanssi_related_no_append":"","_relevanssi_related_not_related":"","_relevanssi_related_posts":"","_relevanssi_noindex_reason":"","footnotes":""},"categories":[367],"tags":[],"class_list":["post-133666","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-cca","news_type-press-release"],"acf":{"block_editor":[{"acf_fc_layout":"code","code":"<div style=\"padding:40% 0 0 0;position:relative;\"><iframe src=\"https:\/\/player.vimeo.com\/video\/1163693900?badge=0&amp;autopause=0&amp;player_id=0&amp;app_id=58479&amp;autoplay=1&amp;muted=1&amp;loop=1\" frameborder=\"0\" allow=\"autoplay; fullscreen; picture-in-picture; clipboard-write; encrypted-media; web-share\" referrerpolicy=\"strict-origin-when-cross-origin\" style=\"position:absolute;top:0;left:0;width:100%;height:100%;\" title=\"_Video Seamless_M31_c.Keith Miller, Caltech IPAC - SELab\"><\/iframe><\/div>\r\n"},{"acf_fc_layout":"text","text":"<span style=\"font-family: 'Univers Next W01', Helvetica, Ariel, sans-serif; font-size: 15px; display: block;\">An animation of a star that collapsed, forming a black hole. The black hole is at the center, unseen. Surrounding it is a dust shell moving away from the black hole and gas being pulled toward it. <span style=\"color: #666;\">Keith Miller, Caltech\/IPAC - SELab<\/span><\/span>\r\n\r\nAstronomers have watched a dying star fail to explode as a supernova, instead collapsing into a black hole. The remarkable sighting is the most complete observational record ever made of a star\u2019s transformation into a black hole, allowing astronomers to construct a comprehensive physical picture of the process.\r\n\r\nCombining recent observations of the star with over a decade of archival data, the astronomers confirmed and refined theoretical models of how such massive stars turn into black holes. The team found that the star failed to explode as a supernova at the end of its life; instead, the star\u2019s core collapsed into a black hole, slowly expelling its turbulent outer layers in the process.\r\n\r\nThe results, <a href=\"https:\/\/doi.org\/10.1126\/science.adt4853\">published February 12 in <em>Science<\/em><\/a>, are already generating excitement as a rare glimpse into the mysterious origins of black holes. The discovery will help explain why some massive stars turn into black holes when they die, while others don\u2019t.\r\n\r\n\u201cThis is just the beginning of the story,\u201d says <a href=\"https:\/\/www.simonsfoundation.org\/people\/kishalay-de\/\">Kishalay De<\/a>, an associate research scientist at the Simons Foundation\u2019s <a href=\"https:\/\/www.simonsfoundation.org\/flatiron\/\">Flatiron Institute<\/a> and lead author on the new study. Light from dusty debris surrounding the newborn black hole, he says, \u201cis going to be visible for decades at the sensitivity level of telescopes like the James Webb Space Telescope, because it\u2019s going to continue to fade very slowly. And this may end up being a benchmark for understanding how stellar black holes form in the universe.\u201d\r\n\r\nThe now-deceased star, called M31-2014-DS1, is located around 2.5 million light-years away from Earth in the neighboring Andromeda Galaxy. De and his collaborators analyzed measurements of the star from NASA\u2019s NEOWISE project and other ground- and space-based telescopes for a period spanning 2005 to 2023. They found that M31-2014-DS1\u2019s infrared light began brightening in 2014. Then in 2016, the star swiftly dimmed far below its original luminosity in barely a year.\r\n\r\nObservations in 2022 and 2023 showed that the star essentially vanished in visible and near-infrared light, becoming one ten-thousandth as bright in these wavelengths. Its remnant is now only detectable in mid-infrared light, where it shines at a mere one-tenth as bright as before.\r\n\r\nDe says, \u201cThis star used to be one of the most luminous stars in the Andromeda Galaxy, and now it was nowhere to be seen. Imagine if the star Betelgeuse suddenly disappeared. Everybody would lose their minds! The same kind of thing [was] happening with this star in the Andromeda Galaxy.\u201d\r\n\r\nComparing these observations with theoretical predictions, the researchers concluded that the star\u2019s dramatic fading to such a small fraction of its original total brightness provides strong evidence that its core collapsed and became a black hole.\r\n\r\nStars fuse hydrogen into helium in their cores, and that process generates outward pressure to balance the incessant inward pull of gravity. When a massive star roughly 10 or more times heavier than our sun begins to run out of fuel, the balance between inward and outward forces is disrupted. Gravity begins to collapse the star, and its core succumbs first to form a dense neutron star at the center.\r\n\r\nOften, the emission of neutrinos in this process generates a powerful shock wave that is explosive enough to rip apart most of the core and outer layers in a supernova. However, if the neutrino-powered shock wave fails to push the stellar material out, theory has long suggested that most of the stellar material would instead fall back into the neutron star, forming a black hole.\r\n\r\n\u201cWe\u2019ve known for almost 50 years now that black holes exist,\u201d says De, \u201cyet we are barely scratching the surface of understanding which stars turn into black holes and how they do it.\u201d\r\n\r\nThe observations and analysis of M31-2014-DS1 enabled the team to reinterpret observations of a similar star, NGC 6946-BH1. This led to an important breakthrough in understanding what had happened to the outer layers that had enveloped the star after it failed to go supernova and collapsed to a black hole. The overlooked element? Convection.\r\n\r\nConvection is a byproduct of the vast temperature differences inside the star. Material near the star\u2019s center is extremely hot, while the outer regions are much cooler. This differential causes gases within the star to move from hotter to cooler regions.\r\n\r\nWhen the star\u2019s core collapses, the gas in its outer layers is still moving rapidly due to this convection. Theoretical models developed by astronomers at the Flatiron Institute have shown that this prevents most of the outer layers from falling directly in; instead, the innermost layers orbit outside of the black hole and drive the ejection of the outermost layers of the convective region.\r\n\r\nThe ejected material cools as it moves farther from the hot material around the black hole. This cool material readily forms dust as atoms and molecules combine. The dust obscures the hot gas orbiting the black hole, warming the dust and producing an observable brightening in infrared wavelengths. This lingering red glow is visible for decades after the star itself disappears.\r\n\r\nCo-author and Flatiron Research Fellow <a href=\"https:\/\/www.simonsfoundation.org\/people\/andrea-antoni\/\">Andrea Antoni<\/a> previously developed the theoretical predictions for these convection models. With the striking observational evidence from M31-2014-DS1, she says, \u201cthe accretion rate \u2014 the rate of material falling in \u2014 is much slower than if the star imploded directly in. This convective material has angular momentum, so it circularizes around the black hole. Instead of taking months or a year to fall in, it\u2019s taking decades. And because of all this, it becomes a brighter source than it would be otherwise, and we observe a long delay in the dimming of the original star.\u201d\r\n\r\nSimilar to water swirling around a bathtub drain rather than flowing straight down, the gas in motion around this newly formed black hole continues in its chaotic orbit even as it\u2019s slowly pulled inward. Thus, the halted infall generated by convection prevents the entire star from collapsing directly into the newborn black hole. Instead, the researchers propose that even after the core promptly implodes, part of the outflowing material slowly falls back over many decades.\r\n\r\nOnly about one percent of the original stellar envelope gas falls into the black hole, powering the light that emanates from it today, the researchers estimate.\r\n\r\nWhile parsing the observations of M31-2014-DS1, De and his team also reevaluated a similar star, NGC 6946-BH1, categorized 10 years ago. In the new paper, they present striking evidence explaining why this star followed a similar pattern. M31-2014-DS1 initially stood out as an \u201coddball,\u201d De says, yet it now appears to be just one member in a class of objects \u2014 including NGC 6946-BH1.\r\n\r\n\u201cIt\u2019s only with these individual jewels of discovery that we start putting together a picture like this,\u201d De says."},{"acf_fc_layout":"divider"},{"acf_fc_layout":"subtitle","title":"Information for Press","is_chapter":false,"is_inline":false,"margin_bottom":""},{"acf_fc_layout":"text","text":"For more information, please contact <a href=\"mailto:press@simonsfoundation.org\" target=\"_blank\" rel=\"noopener\">press@simonsfoundation.org<\/a>.\r\n<ul>\r\n \t<li><a href=\"https:\/\/doi.org\/10.1126\/science.adt4853\">Link to scientific paper<\/a><\/li>\r\n \t<li><a href=\"https:\/\/www.dropbox.com\/scl\/fo\/ev4nfm0xp69bjr2rvpfhi\/AKOSdZkzzcH6ovlQ9EH8RiM?rlkey=x3hyv9jqzfwamqnk5cjeueysx&amp;st=mxse6m54&amp;dl=0\">Link to full-resolution multimedia<\/a><\/li>\r\n<\/ul>"}]},"_links":{"self":[{"href":"https:\/\/www.simonsfoundation.org\/wp-json\/wp\/v2\/posts\/133666"}],"collection":[{"href":"https:\/\/www.simonsfoundation.org\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.simonsfoundation.org\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.simonsfoundation.org\/wp-json\/wp\/v2\/users\/7"}],"replies":[{"embeddable":true,"href":"https:\/\/www.simonsfoundation.org\/wp-json\/wp\/v2\/comments?post=133666"}],"version-history":[{"count":21,"href":"https:\/\/www.simonsfoundation.org\/wp-json\/wp\/v2\/posts\/133666\/revisions"}],"predecessor-version":[{"id":134795,"href":"https:\/\/www.simonsfoundation.org\/wp-json\/wp\/v2\/posts\/133666\/revisions\/134795"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.simonsfoundation.org\/wp-json\/wp\/v2\/media\/133737"}],"wp:attachment":[{"href":"https:\/\/www.simonsfoundation.org\/wp-json\/wp\/v2\/media?parent=133666"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.simonsfoundation.org\/wp-json\/wp\/v2\/categories?post=133666"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.simonsfoundation.org\/wp-json\/wp\/v2\/tags?post=133666"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}