{"id":781059,"date":"2024-04-18T18:15:50","date_gmt":"2024-04-18T23:15:50","guid":{"rendered":"http:\/\/spaceweekly.com\/?p=781059"},"modified":"2024-04-18T18:15:50","modified_gmt":"2024-04-18T23:15:50","slug":"meet-gaia-bh3-our-galaxys-most-massive-stellar-black-hole","status":"publish","type":"post","link":"https:\/\/spaceweekly.com\/?p=781059","title":{"rendered":"Meet Gaia BH3, our galaxy\u2019s most massive stellar black hole"},"content":{"rendered":"<p> <br \/>\n<\/p>\n<div>\n<p><iframe loading=\"lazy\" title=\"The Most Massive Stellar BLACK HOLE in the Milky Way!\" width=\"1110\" height=\"833\" src=\"https:\/\/www.youtube.com\/embed\/l4JdxYb3Cjs?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><br \/><em>EarthSky\u2019s Deborah Byrd created this 1-minute video summary for you on Gaia BH3!<\/em><\/p>\n<ul>\n<li><strong>The most massive stellar black hole in the Milky Way<\/strong> is now Gaia BH3. It has a mass 33 times that of our sun. <\/li>\n<li><strong>Gaia BH3 is located 2,000 light-years away<\/strong> in the constellation Aquila, making it the 2nd-closest known black hole to Earth.<\/li>\n<li><strong>The discovery challenges previous theories<\/strong>, suggesting that high-mass black holes may form from metal-poor stars, supported by Gaia\u2019s observation of a metal-poor companion star to Gaia BH3.<\/li>\n<\/ul>\n<p>EarthSky needs YOUR help to keep going. Your support, comments, photos, suggestions for stories \u2013 and your stories on how you use, value and love EarthSky\u2019s content \u2013 all make our days bright. Thank you for donating!<\/p>\n<h3>Meet Gaia BH3<\/h3>\n<p>The European Southern Observatory said on April 16, 2024, that its astronomers have helped confirm the discovery of the most massive stellar black hole yet discovered in our home galaxy, the Milky Way. They call the object Gaia BH3. And it isn\u2019t the Milky Way\u2019s <em>most<\/em> massive black hole. Instead, Sagittarius A*, the supermassive black hole at the Milky Way\u2019s center, holds that title with some four million times our sun\u2019s mass. Gaia BH3 has only 33 times our sun\u2019s mass. It\u2019s a pipsqueak in contrast to Sagittarius A*. But it\u2019s the most massive black hole known in the Milky Way <em>that formed from the collapse of a single star.<\/em><\/p>\n<p>Gaia BH3 is relatively nearby at 2,000 light-years away. It\u2019s the 2nd-closest known black hole to Earth. It\u2019s located in the direction to the constellation Aquila the Eagle, a noticeable constellation in the Northern Hemisphere summer sky. Astronomer Pasquale Panuzzo, of the National Centre for Scientific Research (CNRS) in Paris, led the collaboration that discovered the massive black hole. He commented:<\/p>\n<blockquote>\n<p>No one was expecting to find a high-mass black hole lurking nearby, undetected so far. This is the kind of discovery you make once in your research life.<\/p>\n<\/blockquote>\n<p>The research study, led by Panuzzo, was published on April 16 in the journal <em>Astronomy &amp; Astrophysics<\/em>. <\/p>\n<figure id=\"attachment_471911\" aria-describedby=\"caption-attachment-471911\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><figcaption id=\"caption-attachment-471911\" class=\"wp-caption-text\">Meet Gaia BH3, the most massive stellar black hole, or a black hole formed by the gravitational collapse of a star, in our Milky Way galaxy. The European Space Agency\u2019s mighty Gaia spacecraft found it thanks to the wobbling motion it induces on a companion star. This artist\u2019s impression shows the orbits of both the star and the black hole orbiting their common center of gravity. Image via ESO\/ L. Cal\u00e7ada.<\/figcaption><\/figure>\n<h3>The amazing Gaia mission<\/h3>\n<p>Now for a word of praise about Gaia, the European Space Agency\u2019s astrometry mission, launched in 2013. <\/p>\n<p>Gaia\u2019s job is to scan the sky repeatedly, observing each of its targeted stars many times over. By the time of its 2nd data release in 2018, Gaia had measurements on 1.7 billion stars! <\/p>\n<p>And the insights about our galaxy revealed by Gaia\u2019s measurements have been nothing short of spectacular. For example, we\u2019ve known our sun and all the stars in the Milky Way are moving continuously in great orderly masses around the center of our galaxy. We\u2019ve known that, but we didn\u2019t have many details about how each star moves, until Gaia. How could we? The data for so many stars would be (are) massive. Collecting the data, storing it and analyzing it requires today\u2019s spacecraft and computer technologies. And that\u2019s where Gaia comes in.<\/p>\n<p>You can read many stories about new insights made possible by Gaia here.<\/p>\n<figure id=\"attachment_471939\" aria-describedby=\"caption-attachment-471939\" style=\"width: 800px\" class=\"wp-caption alignnone\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/earthsky.org\/upl\/2024\/04\/Gaia_mapping_the_stars_of_the_Milky_Way_ESA-2-e1713344765819.jpg\" alt=\"Star-strewn sky with fuzzy diagonal band of stars and and a gleaming cylindrical spacecraft.\" width=\"800\" height=\"530\" class=\"size-full wp-image-471939\"\/><figcaption id=\"caption-attachment-471939\" class=\"wp-caption-text\">Artist\u2019s concept of Gaia in space. Image via ESA.<\/figcaption><\/figure>\n<h3>How Gaia spied the black hole<\/h3>\n<p>Black holes are \u2026 black. No light escapes them. So how did Gaia discover our galaxy\u2019s most massive stellar-mass black hole? It was able to do it because the hole imposes a \u201cwobbling\u201d motion on its companion star. In the course of Gaia\u2019s acquiring measurements \u2013 and as astronomers analyzed those measurements \u2013 the wobble became noticeable to the astronomy world. And then, ESO said:<\/p>\n<blockquote>\n<p>Data from the European Southern Observatory\u2019s Very Large Telescope (ESO\u2019s VLT) and other ground-based observatories were used to verify the mass of the black hole, putting it at an impressive 33 times that of the sun.<\/p>\n<\/blockquote>\n<h3>What are stellar-mass black holes?<\/h3>\n<p>As so often happens in astronomy, the theory of black holes preceded our discovery of them. The theory arose from the work of Albert Einstein in 1915, and so, throughout the early part of the 20th century, astronomers wondered if black holes did exist, and how we might find objects that emit no light. Astronomers agreed that, if black holes did exist, they probably formed when massive stars ran out of fuel and collapsed. <\/p>\n<p>The first known black hole was seen in X-rays in 1964, in one of the first rocket flights needed to get high enough up that the X-rays weren\u2019t blocked by Earth\u2019s atmosphere. During this flight, astronomers discovered one of the brightest X-ray sources in the sky. Because it was located in the direction of the constellation Cygnus, they named it Cygnus X-1. This object \u2013 called Cyg X-1 for short \u2013 is now thought to have about 21 times our sun\u2019s mass. <\/p>\n<h3>Do metal-poor stars lead to high-mass black holes?<\/h3>\n<p>So before Gaia GH3, we didn\u2019t know of any black holes in our Milky Way galaxy with 33 stellar masses. But we knew such massive black holes existed, because they\u2019d been found in other galaxies. But the formation of these black holes provided astronomers with a puzzle. These scientists\u2019 statement explained:<\/p>\n<blockquote>\n<p>[Astronomers] theorized that they may form from the collapse of stars with very few elements heavier than hydrogen and helium in their chemical composition. These so-called metal-poor stars are thought to lose less mass over their lifetimes and hence have more material left over to produce high-mass black holes after their death. <\/p>\n<p>But evidence directly linking metal-poor stars to high-mass black holes has been lacking until now.<\/p>\n<p>Stars in pairs tend to have similar compositions, meaning that BH3\u2019s companion holds important clues about the star that collapsed to form this exceptional black hole. UVES data showed that the companion was a very metal-poor star, indicating that the star that collapsed to form BH3 was also metal-poor, just as predicted.<\/p>\n<\/blockquote>\n<figure id=\"attachment_471917\" aria-describedby=\"caption-attachment-471917\" style=\"width: 800px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/earthsky.org\/upl\/2024\/04\/stellar-mass-black-holes-comparison-ESO-e1713302141878.jpg\" alt=\"3 black holes.\" width=\"800\" height=\"450\" class=\"size-full wp-image-471917\"\/><figcaption id=\"caption-attachment-471917\" class=\"wp-caption-text\">Artist\u2019s concept comparing side-by-side 3 stellar black holes in our galaxy: Gaia BH1, Cygnus X-1 and Gaia BH3. Their masses are 10, 21 and 33 times that of our sun, respectively. Gaia BH3 is the most massive stellar black hole found to date in the Milky Way. The radii of the black holes are directly proportional to their masses, but note that the black holes themselves have not been directly imaged. Why? Because not even light can escape a black hole. Image via ESO\/ M. Kormesser.<\/figcaption><\/figure>\n<p>Bottom line: Astronomers have discovered the most massive stellar black hole yet discovered in our home galaxy, the Milky Way. They call the object Gaia BH3.<\/p>\n<p>Source: Discovery of a dormant 33 solar-mass black hole in pre-release Gaia astrometry<\/p>\n<p>Via ESO<\/p>\n<p><span class=\"cp-load-after-post\"\/><\/div>\n<div>\n<div class=\"post-author\">\n<h4>Deborah Byrd<\/h4>\n<p>                    View Articles\n                  <\/p><\/div>\n<div class=\"post-tags\">\n<h6 data-udy-fe=\"text_7c58270d\">About the Author:<\/h6>\n<p>Deborah Byrd created the EarthSky radio series in 1991 and founded EarthSky.org in 1994. Prior to that, she had worked for the University of Texas McDonald Observatory since 1976, and created and produced their Star Date radio series. Today, she serves as Editor-in-Chief of this website. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named 3505 Byrd in her honor. In 2020, she won the Education Prize from the American Astronomical Society, the largest organization of professional astronomers in North America. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. &#8220;Being an EarthSky editor is like hosting a big global party for cool nature-lovers,&#8221; she says.<\/p>\n<\/p><\/div>\n<\/p><\/div>\n<p><br \/>\n<br \/><a href=\"https:\/\/earthsky.org\/space\/gaia-bh3-milky-ways-most-massive-stellar-black-hole\/?rand=772280\">Source link <\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>EarthSky\u2019s Deborah Byrd created this 1-minute video summary for you on Gaia BH3! The most massive stellar black hole in the Milky Way is now Gaia BH3. It has a&hellip; <\/p>\n","protected":false},"author":1,"featured_media":781060,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[46],"tags":[],"class_list":["post-781059","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-earth-sky"],"_links":{"self":[{"href":"https:\/\/spaceweekly.com\/index.php?rest_route=\/wp\/v2\/posts\/781059","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/spaceweekly.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/spaceweekly.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/spaceweekly.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/spaceweekly.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=781059"}],"version-history":[{"count":0,"href":"https:\/\/spaceweekly.com\/index.php?rest_route=\/wp\/v2\/posts\/781059\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/spaceweekly.com\/index.php?rest_route=\/wp\/v2\/media\/781060"}],"wp:attachment":[{"href":"https:\/\/spaceweekly.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=781059"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/spaceweekly.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=781059"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/spaceweekly.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=781059"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}