{"id":576037,"date":"2026-01-27T17:14:15","date_gmt":"2026-01-27T20:14:15","guid":{"rendered":"https:\/\/revistapesquisa.fapesp.br\/?p=576037"},"modified":"2026-01-27T17:14:15","modified_gmt":"2026-01-27T20:14:15","slug":"black-hole-with-a-mass-equivalent-to-36-billion-suns-is-one-of-the-largest-ever-found","status":"publish","type":"post","link":"https:\/\/revistapesquisa.fapesp.br\/en\/black-hole-with-a-mass-equivalent-to-36-billion-suns-is-one-of-the-largest-ever-found\/","title":{"rendered":"Black hole with a mass equivalent to 36 billion suns is one of the largest ever found"},"content":{"rendered":"

Astronomers have discovered a black hole with the mass of 36 billion suns at the heart of the Cosmic Horseshoe\u2014a stunning trio of galaxies in the constellation Leo. The discovery, ranking among the most massive black holes ever observed, was reported in the Monthly Notices of the Royal Astronomical Society<\/em> (MNRAS) this August. \u201cFinding such an enormous black hole wasn\u2019t part of the plan,\u201d says lead author Carlos Melo-Carneiro, a Brazilian physicist who recently earned his PhD from the Federal University of Rio Grande do Sul (UFRGS). \u201cFor three months, I was convinced I\u2019d done something wrong.\u201d<\/p>\n

The research began last year while Melo-Carneiro was conducting part of his PhD at the University of Portsmouth in the UK, supported by an exchange fellowship from the Brazilian Federal Agency for Support and Evaluation of Graduate Education (CAPES). His original goal was to study the evolutionary history and dark matter content\u2014which makes up roughly a quarter of the universe\u2019s total mass\u2014of the Cosmic Horseshoe. As part of his research, he estimated the mass of the black hole believed to sit at the center of one of its galaxies\u2014and the result turned out to be surprising. \u201cWe already knew the system hosted a black hole, but our first models capped its mass at around 10 billion suns,\u201d says Thomas Collett, a British astrophysicist at the University of Portsmouth and a coauthor of the study, who also co-supervised Melo-Carneiro\u2019s doctoral research, speaking to Pesquisa FAPESP<\/em>.<\/p>\n

Thanks to a unique feature of the Cosmic Horseshoe, the team could measure the black hole\u2019s mass in two independent ways. One method used stellar velocity measurements\u2014since the faster the stars move near the center, the more massive the black hole must be. The other relied on gravitational lensing, a cosmic optical illusion that warps and magnifies the light of background galaxies. \u201cOur simulations showed that only a black hole about 36 billion solar masses could simultaneously account for the gravitational lensing pattern and the stellar movement we observed,\u201d Melo-Carneiro explains. The team estimates a margin of error of roughly 15 percent.<\/p>\n

\u201cIt\u2019s a fascinating paper, particularly because of how it combines two methods\u2014stellar dynamics and gravitational lensing\u2014to determine the black hole\u2019s mass,\u201d says Rodrigo Nemmen, an astrophysicist at the Institute of Astronomy, Geophysics, and Atmospheric Sciences at the University of S\u00e3o Paulo (IAG-USP), who was not part of the research team.<\/p>\n

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NASA<\/span>In the image, a reddish-orange galaxy appears encircled by a broken blue ring and several blurred structures marked in boxes. The black hole lies at the center of the reddish-orange object\u2014one of three galaxies that make up the systemNASA<\/span><\/p><\/div>\n

Discovered in 2007 as part of the Sloan Digital Sky Survey, the Cosmic Horseshoe ranks among the best-known galactic systems whose visible-light images are warped and magnified by gravitational lensing. Predicted by Albert Einstein (1879\u20131955) in his 1915 general theory of relativity, the lensing phenomenon is caused by gravity\u2014a massive object bending and distorting the fabric of spacetime. That curvature warps the light traversing the perimeter of the object, much like a lens.<\/p>\n

Because of this gravitational lensing effect, the system takes on its distinctive horseshoe shape. Without the lensing, an observer on Earth would see only a single round, reddish-orange galaxy in Leo\u2014not the partially closed blue arc that gives the system its name. That glowing, fire-colored object is a luminous red galaxy, and it\u2019s the closest of the trio\u2014lying about 5 billion light-years from Earth. \u201cThe black hole we measured sits precisely at the center of that galaxy,\u201d explains Cristina Furlanetto, a physicist at the Federal University of Rio Grande do Sul (UFRGS) who is a coauthor of the study and Melo-Carneiro\u2019s PhD advisor.<\/p>\n

With a mass tens of times greater than that of the Milky Way, the galaxy itself behaves as a gravitational lens. It bends and amplifies the light from two much more distant galaxies sitting behind it\u2014one located about 10.4 billion light-years away, and the other roughly 11 billion light-years from us. The system\u2019s blue horseshoe is known in technical jargon as an Einstein ring. The middle galaxy\u2019s light is lensed too, though it doesn\u2019t produce the elegant circular arc that makes the system so striking. Instead, it forms a faint, blurred patch near the bright red galaxy and a bluish streak above the horseshoe\u2014features visible in the smaller inset image highlighting details of the system.<\/p>\n

Black holes are cosmic objects so dense that, beyond a certain boundary, nothing\u2014not even light\u2014can escape their overwhelming gravity. Astrophysicists now believe that nearly every galaxy, and possibly all of them, harbor a supermassive black hole at their core. Our own Milky Way hosts a black hole of roughly 4.3 million solar masses, known as Sagittarius A*. The galaxy M87, one of the largest known, contains an even bigger one\u2014about 6.5 billion times the mass of the Sun. The Cosmic Horseshoe\u2019s black hole, by contrast, is dormant. In other words, it consumes almost none of the visible matter swirling nearby. For the most part, it lies silent. This very stillness makes such a cosmic heavyweight especially difficult to study.<\/p>\n

One key question astronomers hope to answer is how the luminous red galaxy and its colossal black hole evolved. Did they grow together or independently? Did they emerge in tandem, or in distinct eras? These are among the mysteries the UFRGS research team now plans to explore in future research.<\/p>\n

The story above was published with the title “A galactic heavyweight<\/strong>” in issue 356 of October\/2025.<\/p>\n

Scientific article<\/strong>
\nMELO-CARNEIRO, C. R. et al.<\/em> Unveiling a 36 billion solar mass black hole at the centre of the Cosmic Horseshoe gravitational lens<\/a>. Monthly Notices of the Royal Astronomical Society<\/strong>. Aug. 4, 2025.<\/p>\n","protected":false},"excerpt":{"rendered":"Discovery was made at the center of one of the galaxies in the system known as the Cosmic Horseshoe","protected":false},"author":13,"featured_media":576047,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"footnotes":""},"categories":[159],"tags":[205],"coauthors":[101],"class_list":["post-576037","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-science","tag-astronomy"],"acf":[],"_links":{"self":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/posts\/576037","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/users\/13"}],"replies":[{"embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/comments?post=576037"}],"version-history":[{"count":1,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/posts\/576037\/revisions"}],"predecessor-version":[{"id":576051,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/posts\/576037\/revisions\/576051"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/media\/576047"}],"wp:attachment":[{"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/media?parent=576037"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/categories?post=576037"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/tags?post=576037"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/revistapesquisa.fapesp.br\/en\/wp-json\/wp\/v2\/coauthors?post=576037"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}