Astronomers decided to track that glow second by second. <\/p>\n They watched how the light brightened and dimmed near the event horizon of Sgr A*, because those changes reveal what the gas and magnetic fields are doing in that extreme environment.<\/p>\n Webb telescope studies Sgr A*<\/p>\n To study this activity, the James Webb Space Telescope (JWST<\/a>) used its Near-Infrared Camera (NIRCam<\/a>) to look at Sgr A* in two infrared colors at the same time: 2.1 micrometers and 4.8 micrometers. <\/p>\n That two-channel view helps us separate small shifts in energy. During several observing sessions over the past two years, Webb collected about two full days of continuous data.<\/p>\n Those uninterrupted runs let the team build light curves, which plot brightness against time. The curves showed steady activity. The brightness flickered on very short timescales and, at intervals, jumped into stronger flares.<\/p>\n Two colors, tiny delays<\/p>\n Watching both infrared channels together gave a key clue. The two wavelengths rose and fell together, but not perfectly. <\/p>\n The shorter wavelength, 2.1 micrometers, usually changed first. The longer wavelength, 4.8 micrometers, followed after a short delay \u2013 sometimes a few seconds, sometimes tens of seconds.<\/p>\n This brief lag points to a clear picture. Near the black hole<\/a>, electrons gain energy quickly and radiate more strongly at shorter wavelengths. As they lose energy, their emission shifts to longer wavelengths.<\/p>\n This process \u2013 charged particles spiraling along magnetic field lines at nearly the speed of light \u2013 is called synchrotron radiation<\/a>.<\/p>\n The data point to two layers of behavior near Sgr A*. First, we see constant, low-level variability \u2013 a \u201cbackground\u201d flicker driven by turbulence in the hot gas close to the event horizon. <\/p>\n Turbulence means the flow does not move in smooth, circular orbits. It pulls and stretches different regions of the flow, heating electrons and producing small, persistent changes in brightness.<\/p>\n Second, we see sharper flares. Twisted magnetic field lines can snap and reconnect as the flow churns. Magnetic reconnection releases stored magnetic energy into nearby particles, accelerating electrons<\/a> in a burst.<\/p>\n Those energized electrons produce the brighter flares, and the timing and color changes of those flares match what Webb recorded. <\/p>\n The same mechanism powers solar flares, but the gravity and conditions around Sgr A* drive it to higher extremes.<\/p>\n Timing points to the edge<\/p>\n Short timescales matter here. For a black hole with a few million solar masses, matter orbiting just outside the event horizon completes an orbit in tens of minutes. <\/p>\n Webb saw rapid changes<\/a> and inter\u2011wavelength delays on sub\u2011minute scales \u2013 comparable to the light\u2011crossing time of a region only a few black hole radii wide.<\/p>\n That timing ties the emission to gas very close to the event horizon, not to material far from the center.<\/p>\n Webb\u2019s long, steady stares captured both the jittery micro\u2011variations and the larger outbursts in the same continuous sequences. <\/p>\n That coherence allowed the team to test physical models against a single, uninterrupted record instead of piecing together events later.<\/p>\n Measuring two wavelengths together gives us more than an extra data stream \u2013 it gives us a clock. When one channel consistently leads the other by seconds, the time order constrains how electrons gain and lose energy.<\/p>\n These timing data constrain the magnetic field and particle energies<\/a> described above. Together, they show that the near\u2011horizon environment acts like a natural particle accelerator.<\/p>\n Overall, the picture is consistent. Gas shed by nearby stars drifts inward and forms a hot, magnetized flow around the black hole. <\/p>\n Turbulence sets the baseline variability. Periodic magnetic reconnection injects extra energy, speeds up electrons, and triggers bright flares.<\/p>\n This approach \u2013 watching the light curves instead of single snapshots \u2013 turns the region around Sgr A* from a static scene into an evolving system. <\/p>\n The timing and color together convert brightness flickers into measurements of particle energy, magnetic fields, and size.<\/p>\n Lessons from Sgr A* flares<\/p>\n The next step is to gather longer, continuous light curves that cover a full day. With that coverage, astronomers can search for subtler patterns, such as repeating orbital signatures or connections between infrared flares and X\u2011ray outbursts that may occur at the same time.<\/p>\n Even with the current dataset, Webb has changed our view of the source. Sgr A* no longer seems like a distant, mysterious \u201csometimes flaring\u201d object. <\/p>\n With two carefully chosen infrared channels, long sequences, and second\u2011by\u2011second timing, it now appears as an active, magnetized flow that we can monitor as it evolves.<\/p>\n The full study was published in The Astrophysical Research Letters<\/a>.<\/p>\n \u2014\u2013<\/p>\n Like what you read? Subscribe to our newsletter<\/a> for engaging articles, exclusive content, and the latest updates.<\/p>\n Check us out on EarthSnap<\/a>, a free app brought to you by Eric Ralls<\/a> and Earth.com.<\/p>\n \u2014\u2013<\/p>\n","protected":false},"excerpt":{"rendered":"The center of our Milky Way galaxy is anything but calm. A supermassive black hole called Sagittarius A*…\n","protected":false},"author":2,"featured_media":265310,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[23],"tags":[90,416,56,54,55],"class_list":{"0":"post-265309","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-space","8":"tag-science","9":"tag-space","10":"tag-uk","11":"tag-united-kingdom","12":"tag-unitedkingdom"},"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/265309","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/comments?post=265309"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/posts\/265309\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media\/265310"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/media?parent=265309"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/categories?post=265309"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/uk\/wp-json\/wp\/v2\/tags?post=265309"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}
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\n<\/a><\/p>\n![\"This](\"https:\/\/www.newsbeep.com\/uk\/wp-content\/uploads\/2025\/11\/milky-way_sgr-a-black-hole_earth-view_ESO_1s.webp.webp\")
<\/a>This 360-degree panoramic image reveals the plane of our Milky Way Galaxy edge-on from our perspective on Earth, and provides an almost \u201coutside looking in\u201d view of its disk, and central bulge. Scientists have, for the first time ever, successfully observed a mid-IR flare in Sgr A*, the supermassive black hole that resides at the heart of the Milky Way. Click image to enlarge. Credit: ESO, S. BrunierTurbulence and reconnection at work<\/p>\n![\"This](\"https:\/\/www.newsbeep.com\/uk\/wp-content\/uploads\/2025\/11\/milky-way_sgr-a-black-hole_flickers-flares_Webb_1s.webp.webp\")
<\/a>This timelapse video compresses about 9 hours of infrared observations by NASA\u2019s James Webb Space Telescope into 30 seconds. Webb observed the black hole at the center of the Milky Way, known as Sagittarius A* (Sgr A*). Webb detected both faint flickers and brighter flares (one of which is seen near the end of the video). Credit: NASA, ESA, CSA, Farhad Yusef-Zadeh (Northwestern), Howard Bushouse (STScI), Alyssa Pagan (STScI). Click image to watch the video.Two wavelengths confirm the physics<\/p>\n