{"id":25636,"date":"2025-01-17T19:29:25","date_gmt":"2025-01-17T13:44:25","guid":{"rendered":"https:\/\/www.revoscience.com\/en\/?p=25636"},"modified":"2025-01-17T19:43:43","modified_gmt":"2025-01-17T13:58:43","slug":"x-ray-flashes-from-a-nearby-supermassive-black-hole-accelerate-mysteriously","status":"publish","type":"post","link":"https:\/\/www.revoscience.com\/en\/x-ray-flashes-from-a-nearby-supermassive-black-hole-accelerate-mysteriously\/","title":{"rendered":"X-ray\u00a0flashes from a nearby supermassive black hole accelerate mysteriously\u00a0\u00a0"},"content":{"rendered":"\n

Their source could be the core of a dead star that\u2019s teetering at the black hole\u2019s edge, MIT astronomers report.<\/strong><\/em><\/p>\n\n\n\n

\"\"
In this artist\u2019s rendering, a stream of matter trails a white dwarf orbiting within the innermost accretion disk surrounding 1ES 1927\u2019s supermassive black hole. Credit: Aurore Simonnet \/ Sonoma State University<\/strong><\/em><\/figcaption><\/figure>\n\n\n

Jennifer Chu<\/p><\/div><\/div>\n\n\n

CAMBRIDGE, Mass. — One supermassive black hole has kept astronomers glued to their scopes for the last several years. First came a surprise disappearance, and now, a precarious spinning act. <\/p>\n\n\n\n

The black hole in question is\u00a01ES 1927+654, which is about as massive as a million suns and sits in a galaxy that is 270 million light-years away. In 2018, astronomers at MIT and elsewhere\u00a0observed<\/a>\u00a0that the black hole\u2019s corona\u2014a cloud of whirling, white-hot plasma\u2014suddenly disappeared before reassembling months later. The brief though dramatic shut-off was a first in black hole astronomy.<\/p>\n\n\n\n

Members of the MIT team have now caught the same black hole, exhibiting more unprecedented behavior.\u00a0<\/p>\n\n\n\n

The astronomers have detected flashes of X-rays coming from the black hole at a steadily increasing clip. Over a period of two years, the flashes, at millihertz frequencies, increased from every 18 minutes to every seven minutes. This dramatic speed-up in X-rays has not been seen from a black hole until now.<\/p>\n\n\n\n

The researchers explored a number of scenarios for what might explain the flashes. They believe the most likely culprit is a spinning white dwarf\u2014an extremely compact core of a dead star that is orbiting around the black hole and getting precariously closer to its event horizon, the boundary beyond which nothing can escape the black hole\u2019s gravitational pull. If this is the case, the white dwarf must be pulling off an impressive balancing act, as it could be coming right up to the black hole\u2019s edge without actually falling in.\u00a0<\/p>\n\n\n\n

\u201cThis would be the closest thing that we know of around any black hole,\u201d says Megan Masterson, a graduate student in physics at MIT who co-led the discovery. \u201cThis tells us that objects like white dwarfs may be able to live very close to an event horizon for a relatively extended period of time.\u201d<\/p>\n\n\n\n

The researchers present their\u00a0findings<\/a>\u00a0at\u00a0the 245th meeting of the American Astronomical Society in National Harbor, Maryland, and will publish the results in a forthcoming paper in\u00a0Nature<\/em>.<\/p>\n\n\n\n

If a white dwarf is at the root of the black hole\u2019s mysterious flashing, it would also give off gravitational waves in a range that would be detectable by next-generation observatories such as NASA\u2019s Laser Interferometer Space Antenna (LISA).\u00a0<\/p>\n\n\n\n

“These new detectors are designed to detect oscillations on the scale of minutes, so this black hole system is in that sweet spot,\u201d says co-author Erin Kara, associate professor of physics at MIT. <\/p>\n\n\n\n

The study\u2019s other co-authors include MIT Kavli members Christos Panagiotou, Joheen Chakraborty, Kevin Burdge, Riccardo Arcodia, Ronald Remillard, and Jingyi Wang, along with collaborators from multiple other institutions. <\/p>\n\n\n\n

Nothing normal<\/strong><\/p>\n\n\n\n

Kara and Masterson were part of the team that observed\u00a01ES 1927+654 in 2018, as the black hole\u2019s corona went dark, and then slowly rebuilt itself over time. For a while, the newly reformed corona\u2014a cloud of highly energetic plasma and X-rays\u2014was the brightest\u00a0X-ray-emitting object in the sky.<\/p>\n\n\n\n

\u201cIt was still extremely bright, though it wasn\u2019t doing anything new for a couple of years and was kind of gurgling along. But we felt we had to keep monitoring it because it was so beautiful,\u201d Kara says. \u201cThen we noticed something that has never really been seen before.\u201d<\/p>\n\n\n\n

In 2022, the team looked through observations of the black hole taken by the European Space Agency\u2019s XMM-Newton, a space-based observatory that detects and measures\u00a0X-ray\u00a0emissions from black holes, neutron stars, galactic clusters, and other extreme cosmic sources. They noticed that\u00a0X-rays from the black hole appeared to pulse with increasing frequency. Such \u201cquasi-periodic oscillations\u201d have only been observed in a handful of other supermassive black holes, where\u00a0X-ray flashes appear with regular frequency.\u00a0<\/p>\n\n\n\n

In the case of 1ES 1927+654, the flickering seemed to steadily ramp up, from every 18 minutes to every seven minutes over the span of two years. <\/p>\n\n\n\n

\u201cWe\u2019ve never seen this dramatic variability in the rate at which it\u2019s flashing,\u201d Masterson says. \u201cThis looked absolutely nothing like a normal supermassive black hole.\u201d<\/p>\n\n\n\n

The fact that the flashing was detected in the\u00a0X-ray\u00a0band points to the strong possibility that the source is somewhere very close to the black hole. The innermost regions of a black hole are extremely high-energy environments, where\u00a0X-rays are produced by fast-moving, hot plasma.\u00a0 X-rays are less likely to be seen at farther distances, where gas can circle more slowly in an accretion disk. The cooler environment of the disk can emit optical and ultraviolet light but rarely gives off\u00a0X-rays.\u00a0<\/p>\n\n\n\n

\u201c<\/strong>Seeing something in the\u00a0X-rays is already telling you you\u2019re pretty close to the black hole,\u201d Kara says. \u201cWhen you see variability on the timescale of minutes, that\u2019s close to the event horizon, and the first thing your mind goes to is circular motion and whether something could be orbiting around the black hole.\u201d\u00a0<\/p>\n\n\n\n

X-ray kick-up<\/strong><\/p>\n\n\n\n

Whatever was producing the X-ray flares was doing so at an extremely close distance from the black hole, which the researchers estimate to be within a few million miles of the event horizon.\u00a0<\/p>\n\n\n\n

Masterson and Kara explored models for various astrophysical phenomena that could explain the\u00a0X-ray patterns they observed, including a possibility relating to the black hole\u2019s corona.\u00a0<\/p>\n\n\n\n

\u201cOne idea is that this corona is oscillating, maybe blobbing back and forth, and if it starts to shrink, those oscillations get faster as the scales get smaller,\u201d Masterson says. \u201cBut we\u2019re in the very early stages of understanding coronal oscillations.\u201d<\/p>\n\n\n\n

Another promising scenario, and one that scientists have a better grasp on in terms of the physics involved, has to do with a daredevil of a white dwarf. According to their modeling, the researchers estimate the white dwarf could have been about one-tenth the mass of the sun. In contrast, the supermassive black hole itself is on the order of 1 million solar masses. <\/p>\n\n\n\n

When any object gets this close to a supermassive black hole, gravitational waves are expected to be emitted, dragging the object closer to the black hole. As it circles closer, the white dwarf moves at a faster rate, which can explain the increasing frequency of X-ray oscillations that the team observed. <\/p>\n\n\n\n

The white dwarf is practically at the precipice of no return and is estimated to be just a few million miles from the event horizon. However, the researchers predict that the star will not fall in. While the black hole\u2019s gravity may pull the white dwarf inward, the star is also shedding part of its outer layer into the black hole. This shedding acts as a small kickback, such that the white dwarf\u2014an incredibly compact object itself\u2014can resist crossing the black hole\u2019s boundary.\u00a0<\/p>\n\n\n\n

\u201cBecause white dwarfs are small and compact, they\u2019re very difficult to shred apart, so they can be very close to a black hole,\u201d Kara says. \u201cIf this scenario is correct, this white dwarf is right at the turnaround point, and we may see it get further away.\u201d<\/p>\n\n\n\n

The team plans to continue observing the system with existing and future telescopes to better understand the extreme physics at work in a black hole\u2019s innermost environments. They are particularly excited to study the system once the space-based gravitational-wave detector LISA launches\u2014currently planned for the mid-2020s\u2014as the gravitational waves that the system should give off will be in a sweet spot that LISA can clearly detect.<\/p>\n\n\n\n

\u201cThe one thing I\u2019ve learned with this source is to never stop looking at it because it will probably teach us something new,\u201d Masterson says. \u201cThe next step is just to keep our eyes open.\u201d<\/p>\n\n\n\n

<\/p>\n","protected":false},"excerpt":{"rendered":"

Their source could be the core of a dead star that\u2019s teetering at the black hole\u2019s edge, MIT astronomers report. CAMBRIDGE, Mass. — One supermassive black hole has kept astronomers glued to their scopes for the last several years. First came a surprise disappearance, and now, a precarious spinning act.  The black hole in question is\u00a01ES […]<\/p>\n","protected":false},"author":2,"featured_media":25637,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[20,17],"tags":[],"class_list":["post-25636","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-space-news","category-research"],"featured_image_urls":{"full":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/01\/MIT-EdgeFlares-01-press_0.jpg",900,600,false],"thumbnail":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/01\/MIT-EdgeFlares-01-press_0-200x200.jpg",200,200,true],"medium":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/01\/MIT-EdgeFlares-01-press_0-600x400.jpg",600,400,true],"medium_large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/01\/MIT-EdgeFlares-01-press_0-768x512.jpg",750,500,true],"large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/01\/MIT-EdgeFlares-01-press_0-675x450.jpg",675,450,true],"1536x1536":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/01\/MIT-EdgeFlares-01-press_0.jpg",900,600,false],"2048x2048":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/01\/MIT-EdgeFlares-01-press_0.jpg",900,600,false],"ultp_layout_landscape_large":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/01\/MIT-EdgeFlares-01-press_0.jpg",900,600,false],"ultp_layout_landscape":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/01\/MIT-EdgeFlares-01-press_0-870x570.jpg",870,570,true],"ultp_layout_portrait":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/01\/MIT-EdgeFlares-01-press_0-600x600.jpg",600,600,true],"ultp_layout_square":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/01\/MIT-EdgeFlares-01-press_0-600x600.jpg",600,600,true],"newspaper-x-single-post":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/01\/MIT-EdgeFlares-01-press_0-760x490.jpg",760,490,true],"newspaper-x-recent-post-big":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/01\/MIT-EdgeFlares-01-press_0-550x360.jpg",550,360,true],"newspaper-x-recent-post-list-image":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/01\/MIT-EdgeFlares-01-press_0-95x65.jpg",95,65,true],"web-stories-poster-portrait":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/01\/MIT-EdgeFlares-01-press_0.jpg",640,427,false],"web-stories-publisher-logo":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/01\/MIT-EdgeFlares-01-press_0.jpg",96,64,false],"web-stories-thumbnail":["https:\/\/www.revoscience.com\/en\/wp-content\/uploads\/2025\/01\/MIT-EdgeFlares-01-press_0.jpg",150,100,false]},"author_info":{"info":["Jennifer Chu"]},"category_info":"Space\/ AstroPhysics<\/a> Research<\/a>","tag_info":"Research","comment_count":"0","_links":{"self":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts\/25636","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/comments?post=25636"}],"version-history":[{"count":4,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts\/25636\/revisions"}],"predecessor-version":[{"id":25642,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/posts\/25636\/revisions\/25642"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/media\/25637"}],"wp:attachment":[{"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/media?parent=25636"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/categories?post=25636"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.revoscience.com\/en\/wp-json\/wp\/v2\/tags?post=25636"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}