Webb Catches Mysterious Light Flares Around Milky Way's Supermassive Black Hole
Between spotting galaxies that shouldn't exist, capturing the interstellar medium with unprecedented clarity, and identifying new worlds, the James Webb Space Telescope is a busy observatory. But as it orbits the Sun, Webb has kept a close eye on one of the most obscure pieces of our galaxy: Sagittarius A*, the supermassive black hole at the center of the Milky Way. By capturing the longest and most detailed Sag A* observations yet, Webb has allowed astronomers to catch a constant light show around the black hole's accretion disk, which draws in Sag A*'s cosmic meals.
In a study published Tuesday in The Astrophysical Journal Letters, an international team of researchers from several space science organizations shared that Webb's NIRCam (Near-InfraRed Camera) spotted many pops of light near Sag A* across 48 hours of observation. These flashes, which varied in strength, appeared to flare from the inner edge of the black hole's accretion disk.
Flares aren't unusual near supermassive black holes, so on its own, the identification of light flares around Sag A* wouldn't have been particularly exciting. What was odd about the team's findings was that Sag A*'s light show never appeared to stop, even as the team studied the flashes over seven 8-to-10-hour observation periods between 2023 and 2024. The only variables they noticed were in wavelength and length of time—data that, thanks to NIRCam's dual modules, could be captured simultaneously during a single session.
"Flares are expected to happen in essentially all supermassive black holes, but our black hole is unique," said astrophysicist and lead study author Farhad Yusef-Zadeh in a Northwestern University statement. "It is always bubbling with activity and never seems to reach a steady state. We observed the black hole multiple times…and we noticed changes in every observation. We saw something different each time, which is really remarkable. Nothing ever stayed the same."
Yusef-Zadeh and his colleagues believe the flares could be the product of the same phenomenon that produces sporadic flashes near other black holes: feisty accretion disks. These swirling disks of gas and dust gravitationally pull matter toward the black hole, eventually tipping that material past the point of no return (the black hole's event horizon). This steady stream of snacks allows the black hole to grow in mass. Every now and then, turbulence within the accretion disk squeezes the disk's plasma, triggering a quick burst of radiation.
"It's similar to how the Sun's magnetic field gathers, compresses, and then erupts a solar flare," Yusef-Zadeh told NASA. "Of course, the processes are more dramatic because the environment around a black hole is much more energetic and much more extreme. But the Sun's surface also bubbles with activity."
But an even more powerful force could be behind Sag A*'s larger flares. When two magnetic fields collide in space, they release energy in the form of accelerated particles. These particles travel so fast that they emit bright bursts of radiation, according to NASA. If "magnetic reconnection events" are happening in Sag A*'s accretion disk, that could explain the more aggressive pops of light.
In the future, the researchers hope to use Webb's NIRCam to observe Sag A* for 24 hours straight. Only a long, uninterrupted period like this would allow the team to see whether the accretion disk's light show is based on any particular pattern or is truly random.
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Yahoo
5 hours ago
- Yahoo
A surprising study revealed biological activity on a distant planet. Weeks later, scientists say there's more to the story
Sign up for CNN's Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. A tiny sign revealed in April seemed like it might change the universe as we know it. Astronomers had detected just a hint, a glimmer of two molecules swirling in the atmosphere of a distant planet called K2-18b — molecules that on Earth are produced only by living things. It was a tantalizing prospect: the most promising evidence yet of an extraterrestrial biosignature, or traces of life linked to biological activity. But only weeks later, new findings suggest the search must continue. 'It was exciting, but it immediately raised several red flags because that claim of a potential biosignature would be historic, but also the significance or the strength of the statistical evidence seemed to be too high for the data,' said Dr. Luis Welbanks, a postdoctoral research scholar at Arizona State University's School of Earth and Space Exploration. While the molecules identified on K2-18b by the April study — dimethyl sulfide, or DMS, and dimethyl disulfide, or DMDS — are associated largely with microbial organisms on our planet, scientists point out that the compounds can also form without the presence of life. Now, three teams of astronomers not involved with the research, including Welbanks, have assessed the models and data used in the original biosignature discovery and got very different results, which they have submitted for peer review. Meanwhile, the lead author of the April study, Nikku Madhusudhan, and his colleagues have conducted additional research that they say reinforces their previous finding about the planet. And it's likely that additional observations and research from multiple groups of scientists are on the horizon. The succession of research papers revolving around K2-18b offers a glimpse of the scientific process unfolding in real time. It's a window into the complexities and nuances of how researchers search for evidence of life beyond Earth — and shows why the burden of proof is so high and difficult to reach. Located 124 light-years from Earth, K2-18b is generally considered a worthy target to scour for signs of life. It is thought to be a Hycean world, a planet entirely covered in liquid water with a hydrogen-rich atmosphere, according to previous research led by Madhusudhan, a professor of astrophysics and exoplanetary science at the University of Cambridge's Institute of Astronomy. And as such, K2-18b has rapidly attracted attention as a potentially habitable place beyond our solar system. Convinced of K2-18b's promise, Madhusudhan and his Cambridge colleagues used observations of the planet by the largest space telescope in operation, the James Webb Space Telescope, to study the planet further. But two scientists at the University of Chicago — Dr. Rafael Luque, a postdoctoral scholar in the university's department of astronomy and astrophysics, and Michael Zhang, a 51 Pegasi b / Burbidge postdoctoral fellow — spotted some problems with what they found. After reviewing Madhusudhan and his team's April paper, which followed up on their 2023 research, Luque and Zhang noticed that the Webb data looked 'noisy,' Luque said. Noise, caused by imperfections in the telescope and the rate at which different particles of light reach the telescope, is just one challenge astronomers face when they study distant exoplanets. Noise can distort observations and introduce uncertainties into the data, Zhang said. Trying to detect specific gases in distant exoplanet atmospheres introduces even more uncertainty. The most noticeable features from a gas like dimethyl sulfide stem from a bond of hydrogen and carbon molecules — a connection that can stretch and bend and absorb light at different wavelengths, making it hard to definitively detect one kind of molecule, Zhang said. 'The problem is basically every organic molecule has a carbon-hydrogen bond,' Zhang said. 'There's hundreds of millions of those molecules, and so these features are not unique. If you have perfect data, you can probably distinguish between different molecules. But if you don't have perfect data, a lot of molecules, especially organic molecules, look very similar, especially in the near-infrared.' Delving further into the paper, Luque and Zhang also noticed that the perceived temperature of the planet appeared to increase sharply from a range of about 250 Kelvin to 300 Kelvin (-9.67 F to 80.33 F or -23.15 C to 26.85 C) in research Madhusudhan published in 2023 to 422 Kelvin (299.93 F or 148.85 C) in the April study. Such harsh temperatures could change the way astronomers think about the planet's potential habitability, Zhang said, especially because cooler temperatures persist in the top of the atmosphere — the area that Webb can detect — and the surface or ocean below would likely have even higher temperatures. 'This is just an inference only from the atmosphere, but it would certainly affect how we think about the planet in general,' Luque said. Part of the issue, he said, is that the April analysis didn't include data collected from all three Webb instruments Madhusudhan's team used over the past few years. So Luque, Zhang and their colleagues conducted a study combining all the available data to see whether they could achieve the same results, or even find a higher amount of dimethyl sulfide. They found 'insufficient evidence' of both molecules in the planet's atmosphere. Instead, Luque and Zhang's team spotted other molecules, like ethane, that could fit the same profile. But ethane does not signify life. Arizona State's Welbanks and his colleagues, including Dr. Matt Nixon, a postdoctoral researcher in the department of astronomy at the University of Maryland College Park, also found what they consider a fundamental problem with the April paper on K2-18b. The concern, Welbanks said, was with how Madhusudhan and his team created models to show which molecules might be in the planet's atmosphere. 'Each (molecule) is tested one at a time against the same minimal baseline, meaning every single model has an artificial advantage: It is the only explanation permitted,' Welbanks said. When Welbanks and his team conducted their own analysis, they expanded the model from Madhusudhan's study. '(Madhusudhan and his colleagues) didn't allow for any other chemical species that could potentially be producing these small signals or observations,' Nixon said. 'So the main thing we wanted to do was assess whether other chemical species could provide an adequate fit to the data.' When the model was expanded, the evidence for dimethyl sulfide or dimethyl disulfide 'just disappears,' Welbanks said. Madhusudhan believes the studies that have come out after his April paper are 'very encouraging' and 'enabling a healthy discussion on the interpretation of our data on K2-18b.' He reviewed Luque and Zhang's work and agreed that their findings don't show a 'strong detection for DMS or DMDS.' When Madhusudhan's team published the paper in April, he said the observations reached the three-sigma level of significance, or a 0.3% probability that the detections occurred by chance. For a scientific discovery that is highly unlikely to have occurred by chance, the observations must meet a five-sigma threshold, or below a 0.00006% probability that the observations occurred by chance. Meeting such a threshold will require many steps, Welbanks said, including repeated detections of the same molecule using multiple telescopes and ruling out potential nonbiological sources. While such evidence could be found in our lifetime, it is less likely to be a eureka moment and more a slow build requiring a consensus among astronomers, physicists, biologists and chemists. 'We have never reached that level of evidence in any of our studies,' Madhusudhan wrote in an email. 'We have only found evidence at or below 3-sigma in our two previous studies (Madhusudhan et al. 2023 and 2025). We refer to this as moderate evidence or hints but not a strong detection. I agree with (Luque and Zhang's) claim which is consistent with our study and we have discussed the need for stronger evidence extensively in our study and communications.' In response to the research conducted by Welbanks' team, Madhusudhan and his Cambridge colleagues have authored another manuscript expanding the search on K2-18b to include 650 types of molecules. They have submitted the new analysis for peer review. 'This is the largest search for chemical signatures in an exoplanet to date, using all the available data for K2-18b and searching through 650 molecules,' Madhusudhan said. 'We find that DMS continues to be a promising candidate molecule in this planet, though more observations are required for a firm detection as we have noted in our previous studies.' Welbanks and Nixon were pleased that Madhusudhan and his colleagues addressed the concerns raised but feel that the new paper effectively walks back central claims made in the original April study, Welbanks said. 'The new paper tacitly concedes that the DMS/DMDS detection was not robust, yet still relies on the same flawed statistical framework and a selective reading of its own results,' Welbanks said in an email. 'While the tone is more cautious (sometimes), the methodology continues to obscure the true level of uncertainty. The statistical significance claimed in earlier work was the product of arbitrary modeling decisions that are not acknowledged.' Luque said the Cambridge team's new paper is a step in the right direction because it explores other possible chemical biosignatures. 'But I think it fell short in the scope,' Luque said. 'I think it restricted itself too much into being a rebuttal to the (Welbanks) paper.' Separately, however, the astronomers studying K2-18b agree that pushing forward on researching the exoplanet contributes to the scientific process. 'I think it's just a good, healthy scientific discourse to talk about what is going on with this planet,' Welbanks said. 'Regardless of what any single author group says right now, we don't have a silver bullet. But that is exactly why this is exciting, because we know that we're the closest we have ever been (to finding a biosignature), and I think we may get it within our lifetime, but right now, we're not there. That is not a failure. We're testing bold ideas.'
Yahoo
7 hours ago
- Yahoo
Common menopause medication might prevent breast cancer while treating hot flashes
A drug intended to treat menopause symptoms could double as breast cancer prevention. New research from Northwestern University in Illinois found that Duavee, a Pfizer-made drug, "significantly reduced" breast tissue cell growth, which is a major indicator of cancer progression. A phase 2 clinical trial included 141 post-menopausal women who had been diagnosed with ductal carcinoma in situ (DCIS), also known as stage 0 breast cancer, according to a press release from Northwestern. Prostate Cancer Drug Now Available To More Patients With Aggressive Form Of Disease This non-invasive breast cancer affects more than 60,000 American women each year, often leading to an outcome of invasive breast cancer. The women were separated into two groups — one received Duavee and the other took a placebo for a month before undergoing breast surgery. Read On The Fox News App Duavee is a conjugated estrogen/bazedoxifene (CE/BZA) drug, which combines estrogen with another medication that minimizes the potential harmful side effects of the hormone. "The key takeaway from the study is that CE/BZA slows the growth (proliferation) of cells in milk ducts of DCIS that expressed the estrogen receptor significantly more than placebo," Dr. Swati Kulkarni, lead investigator and professor of breast surgery at Northwestern University Feinberg School of Medicine, told Fox News Digital. Experimental Women's Cancer Drug Boosts Survival Rates In Notable Study Another major finding is that the quality of life did not differ significantly between the two groups, but patients who took the CE/BZA reported fewer hot flashes during the study, she noted. "This would be expected, as the drug is FDA-approved to treat hot flashes." Kulkarni presented the study last week at the American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago. The findings are preliminary and have not yet been published in a medical journal. "What excites me most is that a medication designed to help women feel better during menopause may also reduce their risk of invasive breast cancer," said the doctor, who is also a Northwestern Medicine breast surgeon. Women who face a higher risk of breast cancer — including those who have experienced "high-risk lesions" — and who also have menopausal symptoms are most likely to benefit from the drug, according to Kulkarni. "These women are typically advised against standard hormone therapies, leaving them with few menopausal treatment options," the release stated. The researchers said they are "encouraged" by these early results, but more research is required before the medication can be considered for approval as a breast cancer prevention mechanism. "Our findings suggest that CE/BZA may prevent breast cancer, but larger studies with several years of follow-up are needed before we would know this for sure," Kulkarni told Fox News Digital. Dr. Sheheryar Kabraji, chief of breast medicine at the Roswell Park Comprehensive Cancer Center in Buffalo, New York, was not involved in the study but commented on the findings. "While intriguing, this study is highly preliminary, and more research will be needed before we can conclude that conjugated estrogen/bazedoxifene (CD/BZA), a form of the hormone estrogen commonly prescribed to address symptoms of menopause, prevents invasive breast cancer or is effective at reducing cancer risk," she told Fox News Digital. Click Here To Sign Up For Our Health Newsletter Kabraji also noted that the study focused on reducing levels of one specific protein, "which does not always predict reduced recurrence of breast cancer." "This study did not directly show that CE/BZA treatment reduces the risk of DCIS recurrence or development of invasive cancer," she noted. "Importantly, however, patients who received this therapy experienced no worsening of quality of life, and saw improvement in vasomotor symptoms, such as hot flashes. If found to be effective in preventing breast cancer, CE/BZA is likely to have fewer side effects than current medications used for breast cancer prevention." For more Health articles, visit Lead researcher Kulkarni emphasized that this medication is not for the treatment of invasive breast cancer or DCIS. "Right now, we can say that women who are concerned about their risk of developing breast cancer can consider this medication to treat their menopausal symptoms," she article source: Common menopause medication might prevent breast cancer while treating hot flashes
Fox News
9 hours ago
- Fox News
Common menopause medication might prevent breast cancer while treating hot flashes
A drug intended to treat menopause symptoms could double as breast cancer prevention. New research from Northwestern University in Illinois found that Duavee, a Pfizer-made drug, "significantly reduced" breast tissue cell growth, which is a major indicator of cancer progression. A phase 2 clinical trial included 141 post-menopausal women who had been diagnosed with ductal carcinoma in situ (DCIS), also known as stage 0 breast cancer, according to a press release from Northwestern. This non-invasive breast cancer affects more than 60,000 American women each year, often leading to an outcome of invasive breast cancer. The women were separated into two groups — one received Duavee and the other took a placebo for a month before undergoing breast surgery. Duavee is a conjugated estrogen/bazedoxifene (CE/BZA) drug, which combines estrogen with another medication that minimizes the potential harmful side effects of the hormone. "The key takeaway from the study is that CE/BZA slows the growth (proliferation) of cells in milk ducts of DCIS that expressed the estrogen receptor significantly more than placebo," Dr. Swati Kulkarni, lead investigator and professor of breast surgery at Northwestern University Feinberg School of Medicine, told Fox News Digital. Another major finding is that the quality of life did not differ significantly between the two groups, but patients who took the CE/BZA reported fewer hot flashes during the study, she noted. "This would be expected, as the drug is FDA-approved to treat hot flashes." "What excites me most is that a medication designed to help women feel better during menopause may also reduce their risk of invasive breast cancer." Kulkarni presented the study last week at the American Society of Clinical Oncology (ASCO) Annual Meeting in Chicago. The findings are preliminary and have not yet been published in a medical journal. "What excites me most is that a medication designed to help women feel better during menopause may also reduce their risk of invasive breast cancer," said the doctor, who is also a Northwestern Medicine breast surgeon. Women who face a higher risk of breast cancer — including those who have experienced "high-risk lesions" — and who also have menopausal symptoms are most likely to benefit from the drug, according to Kulkarni. "These women are typically advised against standard hormone therapies, leaving them with few menopausal treatment options," the release stated. The researchers said they are "encouraged" by these early results, but more research is required before the medication can be considered for approval as a breast cancer prevention mechanism. "Our findings suggest that CE/BZA may prevent breast cancer, but larger studies with several years of follow-up are needed before we would know this for sure," Kulkarni told Fox News Digital. Dr. Sheheryar Kabraji, chief of breast medicine at the Roswell Park Comprehensive Cancer Center in Buffalo, New York, was not involved in the study but commented on the findings. "While intriguing, this study is highly preliminary, and more research will be needed before we can conclude that conjugated estrogen/bazedoxifene (CD/BZA), a form of the hormone estrogen commonly prescribed to address symptoms of menopause, prevents invasive breast cancer or is effective at reducing cancer risk," she told Fox News Digital. Kabraji also noted that the study focused on reducing levels of one specific protein, "which does not always predict reduced recurrence of breast cancer." "This study did not directly show that CE/BZA treatment reduces the risk of DCIS recurrence or development of invasive cancer," she noted. "While intriguing, this study is highly preliminary." "Importantly, however, patients who received this therapy experienced no worsening of quality of life, and saw improvement in vasomotor symptoms, such as hot flashes. If found to be effective in preventing breast cancer, CE/BZA is likely to have fewer side effects than current medications used for breast cancer prevention." For more Health articles, visit Lead researcher Kulkarni emphasized that this medication is not for the treatment of invasive breast cancer or DCIS. "Right now, we can say that women who are concerned about their risk of developing breast cancer can consider this medication to treat their menopausal symptoms," she added.
