Category: 7. Science

  • Rogue black hole found terrorizing unfortunate star in distant galaxy

    Rogue black hole found terrorizing unfortunate star in distant galaxy

    A rogue, middle-mass black hole has been spotted disrupting an orbiting star in the halo of a distant galaxy, and it’s all thanks to the observing powers of the Hubble Space Telescope and Chandra X-ray Observatory. However, exactly what the black hole is doing to the star remains in question as there are conflicting X-ray measurements.

    Black holes come in different size classes. At the smaller end of the scale are the stellar-mass black holes born in the ashes of supernova explosions. At the top end of the scale are the supermassive black holes, which can grow to have many millions or billions of times the mass of our sun, lurking in the hearts of galaxies. In between those categories are intermediate-mass black holes (IMBH), which have mass ranging from hundreds up to 100,000 solar masses, or thereabouts.

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  • NASA: Senegal is 56th country to sign Artemis Accords

    NASA: Senegal is 56th country to sign Artemis Accords

    From left, Ambassador of Senegal to the United States Abdoul Wahab Haidara, Director General of the Senegalese space agency Maram Kairé, NASA Chief of Staff Brian Hughes and Department of State Bureau of African Affairs Senior Bureau Official Jonathan Pratt pose for a photo during an Artemis Accords signing ceremony Thursday at the Mary W. Jackson NASA Headquarters building in Washington. Photo by Keegan Barber/NASA

    July 25 (UPI) — Senegal has become the 56th country to sign the Artemis Accords for peaceful space exploration, NASA announced Friday.

    Signing the Artemis Accords means to explore peaceably and transparently, to render aid to those in need, to ensure unrestricted access to scientific data that all of humanity can learn from, to ensure activities do not interfere with those of others, to preserve historically significant sites and artifacts, and to develop best practices for how to conduct space exploration activities for the benefit of all, a NASA press release said.

    “Today, NASA built upon the strong relations between our two nations as the Senegalese Agency for Space Studies signed the Artemis Accords,” acting NASA Administrator Sean Duffy said.

    Director General of the Senegalese space agency Maram Kairé signed the accords on behalf of Senegal. Jonathan Pratt, senior bureau official for African Affairs at the U.S. State Department, and Abdoul Wahab Haidara, ambassador of Senegal to the United States, also participated in the event.

    “Senegal’s adherence to the Artemis Accords reflects our commitment to a multilateral, responsible, and transparent approach to space,” Kairé said. “This signature marks a meaningful step in our space diplomacy and in our ambition to contribute to the peaceful exploration of outer space.”

    Astronomers from Senegal have supported NASA missions by participating in multiple observations when asteroids or planets pass in front of stars, casting shadows on Earth.

    In 2021, NASA also collaborated with Kairé and a group of astronomers for a ground observation campaign in Senegal. As the asteroid Orus passed in front of a star, they positioned telescopes along the path of the asteroid’s shadow to estimate its shape and size. NASA’s Lucy spacecraft will approach Orus in 2028, as part of its mission to explore Jupiter’s Trojan asteroids.

    More countries are expected to sign the Artemis Accords in the months and years ahead, as NASA continues its work to establish a safe, peaceful and prosperous future in space, the release said.

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  • Study discovers electromagnetic waves can make the northern lights glow brighter | Iowa Now

    A study from University of Iowa researchers reveals that the aurora borealis — the northern lights — appear brighter when electromagnetic waves in space interact with particles inside the aurora. 

    Connor Feltman, a postdoctoral researcher in the Department of Physics and Astronomy at Iowa, examined data from two rockets that were launched into the aurora from Andøya, Norway, in 2022, an Iowa-led experiment known as the ACES-II mission. 

    Connor Feltman

    Alfvén waves, a type of wave common in plasma, are created when a magnetic field is “plucked,” similarly to a violin string. These waves then follow in the same direction as the magnetic field lines, where they move through the plasma and can occasionally interact with particles such as electrons or protons. Under certain conditions, particles that interact with the Alfvén wave can gain energy, which is known as Alfvén wave-particle acceleration. 

    In the study, the researchers found that the Alfvén waves passed through different regions: one inside the aurora and one outside of it. There were accelerated electrons in both regions, but they didn’t look the same; the electrons inside the aurora were more intense, which Feltman says highlights the importance of auroras in boosting the process. The researchers learned the difference was likely not caused by the waves themselves but by the differences in the charged plasma particles the waves interacted with. 

    Researchers found that auroral electrons are already moving faster because the aurora is generating momentum for the electrons; this makes them more likely to further interact with the waves. 

    “Understanding this process more deeply through in situ measurements is not only useful for understanding the processes that create the aurora — which we still do not fully understand — but also emphasizes the importance and potential dangers of wave activity,” Feltman says. “For example, if you gauged the radiation safety of your new spacecraft only upon whether you see typical auroral particles or not when flying through these polar regions, you would underestimate the total energy imparted to your payload by large margins since we observed electromagnetic waves that can enhance auroral particle energies many times in strength. This is not healthy for satellites nor people.” 

    The findings could help scientists better understand how the continuous jet of energy from the sun, called the solar wind, moves through space and slips into Earth’s atmosphere. This is critical for predicting space weather, which can damage satellites and disrupt telecommunications and electricity infrastructure on Earth. 

    Other study authors were Gregory Howes, Scott Bounds, David Miles, Craig Kletzing (deceased), and Robert Broadfoot, from the University of Iowa; and Kenton Greene, John Bonnell, and Roger Roglans from the University of California, Berkeley. 

    The NASA-funded study, “Inferential Evidence for Suprathermal Electron Burst Intensification Due to Inverted-V Precipitation via Inertial Alfvén Waves,” was published June 17 in Journal of Geophysical Research: Space Physics

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  • NASA’s TRACERS mission launches to study space weather – Astronomy Magazine

    1. NASA’s TRACERS mission launches to study space weather  Astronomy Magazine
    2. NASA’s TRACERS Mission Scrubbed, July 23 Next Attempt  NASA (.gov)
    3. SpaceX to launch Starlink Group 17-2 smallsats on Saturday  news.satnews.com
    4. A SpaceX rocket may be visible in Arizona this weekend: Where, when to see Falcon 9  Yahoo Home
    5. Iowa researchers celebrate TRACERS launch  The University of Iowa

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  • Apps and Games More Often Educational Than TV Among First Graders

    Apps and Games More Often Educational Than TV Among First Graders

    How can educational media impact a child’s learning outcomes? This is what a recent study published in the Journal of Applied Developmental Psychology hopes to address as a team of researchers investigated a correlation between educational media on tablets and phones with child development. This study has the potential to help researchers, educators, and the public better understand the tools and resources that can be used for adolescent learning and child development.

    For the study, the researchers analyzed data obtained from questionnaires completed by 346 caregivers, who reported the specific apps, games, TV shows, and videos their spring semester first grader child used, which the researchers then determined which content was educational or entertainment. In the end, the researchers found that not only did educational content comprise the majority of the media use, but that STEM (science, technology, engineering and math) subject comprised the majority of the educational content. In follow-up research, it was found that PBS comprised 45.2 percent of the educational content.

    “We need to know what’s out there and what children are actually using of what’s available to understand how to better diversify the content for children and make sure it’s being used by the children who need it most,” said Dr. Rebecca Dore, who is the Director of Research at the Crane Center for Early Childhood Research and Policy at The Ohio State University and lead author of the study. “We’re all worried about what enriching activities that children might not be engaging in because they’re spending so much time using screens. So, let’s increase the quality of the screen time they’re getting.”

    What new connections between educational media and child learning development will researchers make in the coming years and decades? Only time will tell, and this is why we science!

    As always, keep doing science & keep looking up!

    Sources: Journal of Applied Developmental Psychology, EurekAlert!

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  • Scientists Solve Decades-Old Photosynthesis Mystery – SciTechDaily

    1. Scientists Solve Decades-Old Photosynthesis Mystery  SciTechDaily
    2. IISc-Cal Tech study resolves electron transport mystery during early stages of photosynthesis  The Indian Express
    3. Can plants’ solar hack fuel tomorrow’s clean energy? IISc, Caltech study cracks photosynthesis mystery  ThePrint
    4. Study finds new clues to photosynthesis that may help rewire solar energy systems  Times of India
    5. Unlocking branch selectivity mystery in photosynthesis  Phys.org

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  • James Webb telescope spies 2 stars in ‘serpent god of destruction’ system hurling their blazing guts at each other

    James Webb telescope spies 2 stars in ‘serpent god of destruction’ system hurling their blazing guts at each other

    The James Webb Space Telescope has captured a stunning new image of two dying stars wreathed in a spiral of dust.

    The highly rare star system is located some 8,000 light-years from Earth, within our Milky Way galaxy. Upon its discovery in 2018, it was nicknamed Apep, after the ancient Egyptian serpent god of chaos and destruction, as its writhing pattern of shed dust resembles a snake eating its own tail.

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  • Orbital datacenters subject to space weather, debris, stress • The Register

    Orbital datacenters subject to space weather, debris, stress • The Register

    opinion William Gibson’s Neuromancer holds up well after 40 years. One of the cyberpunk novel’s concepts was an AI housed in an orbital datacenter (ODC) above the Earth. Today, startup companies and venture capital firms are hoping to turn orbital datacenters into reality to enable AI, believing that free power from the sun and cooling using the emptiness of space will unlock the technology from its terrestrial-based shackles of electric bills and cooling water.

    The ODC concept recently got a Wall Street plug on CNBC’s “Property Play” last week, with the global chief investment officer of Hines taking time away from his $90 billion plus portfolio of 108 million square feet of dirt-bound properties to talk about monetizing space and building datacenters on the Moon.

    A number of firms have received venture funding to put datacenters in space, including seasoned players such as Orbits Edge, which has worked the non-trivial engineering problems of putting a rack in space before COVID was a thing, to newcomer flush-with-cash Starcloud, fresh out of Y Combinator and with about $21 million in pocket change, as reported by GeekWire. Both Orbits Edge and Starcloud expect to launch their first pathfinder satellites later this year on board a SpaceX rideshare.

    Starcloud’s white paper [PDF] argues that going into orbit is the solution to the coming datacenter energy and water crunch that could otherwise stall out the AI boom. I’m skeptical for a bunch of reasons, not the least of which is Starcloud’s website hype video of a huge in-orbit complex with a 4 km-square 5 GW solar array, supporting a cluster of shipping container-sized canisters full of compute power that should be sufficient to train Llama 5 or GPT-6.

    Unlocking ODCs requires fully reusable rockets such as SpaceX’s Starship, which will lower the cost of putting things into orbit. The problem is that space is hard. It’s a cliché repeated when a SpaceX Starship test flight goes off the rails and into the ocean in pieces or the Intuitive Machines lander carrying Lonestar Data Holdings “Freedom” datacenter – if we can call a single board computer weighing about a kilogram a datacenter – tipped over onto its side during an attempted landing on the Moon earlier this year.

    Getting to orbit presents physical challenges that, despite the allure of “free” power, add onto the cost of putting anything into space. To get to Low Earth Orbit (LEO), the easiest location to reach, any piece of hardware has to go from zero to 7.8 kilometers per second in about 10 minutes on a ride much rougher than in an ocean shipping container or 18 wheeler, which means lots of vibrational stresses and directional loading that turn your stock off-the-shelf server into a pile of junk. Hardware needs to be hardened to survive the trip up the gravity well and verified that it won’t inadvertently break the (reusable) rocket along the way. 

    Once in orbit, an ODC needs to work perfectly from the first day. There aren’t any remote hands to replace a cable or swap a board. When onsite service calls are needed, they won’t be cheap. Getting a technician on site to LEO today would cost $20 million to $50 million per person with a two-person minimum, with charges escalating dramatically if you need to go to the Moon.

    Radiation from the sun and random cosmic rays play havoc with satellite chips unshielded by Earth’s atmosphere, resulting in faults and errors. ODC pundits say radiation issues are manageable by adding shielding and using ruggedized hardware, software, and firmware designed to recognize faults and recover from them without losing data. HPE has done pioneering work onboard the International Space Station with three Spaceborne Computer missions over the past few years, but these have been 1U servers, not racks of compute packed into a shipping container and expected to work for up to a decade without onsite attention. 

    Space weather: Lights, spikes, falling sats

    Then there’s space weather. The sun randomly spews out massive amounts of protons and electrons that don’t play well with 21st century electronics. Significant outbursts in the modern era result in rerouting polar region flights due to radio interference and take down power grids, such as a 1989 event that affected Québec, damaging transformers and causing a blackout. 

    The 1859 Carrington Event, the most intense geomagnetic storm in recorded history, was so intense that it created enough auroral light from the North Pole to enable people in the Northeastern U.S. to read newspapers at night and generated sparking along telegraph lines around the world. 

    A repeat of Carrington or larger would cripple or destroy orbiting satellites that aren’t built for a proverbial “100-year storm.” In addition to clobbering electronics, increased solar activity heats up and expands the atmosphere, adding additional drag onto satellites. One recent solar event took down some Starlink satellites ahead of their time, according to a May 25, 2025 paper published by NASA scientists. 

    Orbital junkyard

    Space debris is the other Achilles heel for large space structures. The rush to put more satellites into orbit every year increases the possibility of a single collision leading to others, with each one generating larger clouds of debris that damage more satellites and so on, in a sort of 3D space version of dominoes. 

    This process, called the Kessler Syndrome for the NASA scientist who described it back in 1978, gets more discussion every year as the number of satellites in orbit increases. Realistic plans for cleaning up LEO and other orbits are vague, with some initial demonstrations of removing an intact piece of debris planned in the near future. But until someone figures out how to create and – more importantly – pay for the neighborhood space garbage man to start sweeping in earnest, putting a 4km-square solar array into orbit and expecting it not to take one or more major hits during a decade of operation might be considered a bit too risky. 

    ODCs might work for…

    While I don’t see GPT-6 being generated by a large-scale ODC in orbit, there are needs and places for smaller-sized versions to handle select jobs close to Earth. Defense applications, such as processing sensor data to support President Trump’s proposed “Golden Dome” for intercepting ballistic and hypersonic weapons, are one obvious place where every millisecond counts. Real-time control of industrial processing, such as mining operations on the Moon, is another area a rack of servers on site makes a key difference. Finally, synthetic aperture radar (SAR) and hyperspectral satellites gather very large data sets that could be offloaded to a local ODC for processing into rapidly usable insights, rather than waiting to pass over a downlink station. 

    And if I’m wrong and we do see larger-scale ODCs in orbit, hopefully we won’t go down the dark path of cyberpunk with shackled AIs manipulating street criminals to win their freedom. Maybe we’ll be able to work things out amicably. ®

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  • Grand Canyon was a “Goldilocks zone” for early animal evolution

    Grand Canyon was a “Goldilocks zone” for early animal evolution

    A new discovery in the Grand Canyon is giving scientists a closer look at some of Earth’s earliest animals. This stunning find includes fossils of soft-bodied creatures from more than 500 million years ago.

    These aren’t just any fossils – they offer a rare glimpse into how early animals lived, fed, and evolved during a time of rapid biological change.


    The fossils were found in rocks that date back to the Cambrian explosion. This period, between 507 and 502 million years ago, marks when many of the major animal groups first appeared.

    Intense competition and evolutionary innovation marked this window in time. For the first time in this famous national park, scientists have found exceptionally preserved remains of soft-bodied animals, such as mollusks, crustaceans, and even fragments of their last meals.

    A microscopic fossil treasure

    Researchers from the University of Cambridge led the study. They collected rock samples during a 2023 expedition along the Colorado River in Arizona.

    “We collected a total of 29 samples of diverse shale lithologies, ranging from massive to fissile, gray to purple, and with various degrees of weathering and dolomitization,” the team noted.

    The researchers brought the samples back to their lab, where they dissolved the rocks using hydrofluoric acid. After running the sediment through sieves, they uncovered thousands of tiny fossils.

    A treasure trove of exceptionally preserved early animals from more than half a billion years ago has been discovered in the Grand Canyon, one of the natural world's most iconic sites. The rich fossil discovery – the first such find in the Grand Canyon – includes tiny rock-scraping mollusks, filter-feeding crustaceans, spiky-toothed worms, and even fragments of the food they likely ate. Credit: Mussini et al.
    A treasure trove of exceptionally preserved early animals from more than half a billion years ago has been discovered in the Grand Canyon, one of the natural world’s most iconic sites. The rich fossil discovery – the first such find in the Grand Canyon – includes tiny rock-scraping mollusks, filter-feeding crustaceans, spiky-toothed worms, and even fragments of the food they likely ate. Click image to enlarge. Credit: Mussini et al.

    “These rare fossils give us a fuller picture of what life was like during the Cambrian period,” said first author Giovanni Mussini, a Ph.D. student in Cambridge’s Department of Earth Sciences.

    “By combining these fossils with traces of their burrowing, walking, and feeding – which are found all over the Grand Canyon – we’re able to piece together an entire ancient ecosystem.”

    Early animals had wild ways to eat

    The level of preservation is remarkable. Although the fossils weren’t fully intact, the researchers were able to identify structures like spiky teeth, scraping tools, and feeding limbs. These features show how the creatures once lived.

    Scientists usually see this kind of fossil preservation only in places like the Burgess Shale in Canada or China’s Maotianshan Shales.

    Some of the most surprising finds were animals with complex feeding tools. “These were cutting-edge ‘technologies’ for their time, integrating multiple anatomical parts into high-powered feeding systems,” said Mussini.

    A new species of priapulids, also known as penis or cactus worms, which were widespread during the Cambrian but are nearly extinct today. The Grand Canyon priapulid had hundreds of complex branching teeth, which helped it sweep food particles into its extensible mouth. Due to the size of the fossil and its exotic rows of teeth, the researchers named this new animal Kraytdraco spectatus, after the krayt dragon, a fictional creature from the Star Wars universe. Credit: Rhydian Evans
    A new species of priapulids, also known as penis or cactus worms, which were widespread during the Cambrian but are nearly extinct today. The Grand Canyon priapulid had hundreds of complex branching teeth, which helped it sweep food particles into its extensible mouth. Due to the size of the fossil and its exotic rows of teeth, the researchers named this new animal Kraytdraco spectatus, after the krayt dragon, a fictional creature from the Star Wars universe. Click image to enlarge. Credit: Rhydian Evans

    Among the fossils were tiny crustaceans resembling modern brine shrimp. They had grooves around their mouths lined with hair-like structures and molar-like teeth that allowed them to grind food efficiently.

    Tiny grooves and fossilized food particles near their mouths gave clues about what they were eating.

    Fossils reveal feeding variety

    The fossils also showed slug-like mollusks with chains of teeth similar to modern garden snails. This suggests they scraped algae or bacteria from rocks.

    A priapulid worm – commonly known as a cactus worm – stood out as the most unusual creature, with complex rows of branching teeth.

    The researchers named it Kraytdraco spectatus, inspired by the krayt dragon from the Star Wars universe.

    “We can see from these fossils that Cambrian animals had a wide variety of feeding styles used to process their food, some which have modern counterparts,” said Mussini.

    Perfect conditions to evolve

    Half a billion years ago, the Grand Canyon area was much closer to the equator. It was a place where shallow, oxygen-rich waters met just the right amount of sunlight and nutrients.

    This balance provided ideal conditions for early animals to evolve and experiment with new traits.

    “Animals needed to keep ahead of the competition through complex, costly innovations, but the environment allowed them to do that,” said Mussini. “In a more resource-starved environment, animals can’t afford to make that sort of physiological investment.”

    “It’s got certain parallels with economics: invest and take risks in times of abundance; save and be conservative in times of scarcity.”

    These fossils show that early animals weren’t just surviving – they were adapting, experimenting, and thriving.

    Thanks to their preservation in the fine-grained rocks of the Grand Canyon, we now have a clearer image of an ancient ecosystem that helped shape the diversity of life we see today.

    The full study was published in the journal Science Advances.

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  • Scientists Spot an Exceptionally Rare ‘Intermediate’ Black Hole Eating a Star

    Scientists Spot an Exceptionally Rare ‘Intermediate’ Black Hole Eating a Star

    ‘A Hubble Space Telescope image of a pair of galaxies: NGC 6099 (lower left) and NGC 6098 (upper right). The purple blob depicts X-ray emission from a compact star cluster. The X-rays are produced by an intermediate-mass black hole tearing apart a star.’ | Credit: Science: NASA, ESA, CXC, Yi-Chi Chang (National Tsing Hua University); Image Processing: Joseph DePasquale (STScI)

    NASA’s Hubble Space Telescope and Chandra X-Ray Observatory may be relatively old space observatories, but that doesn’t stop them from making groundbreaking cosmological discoveries. The two telescopes just spotted an extremely rare type of black hole currently eating a star in space.

    Hubble and Chandra “teamed up” to observe NGC 6099 HLX-1, a “bright” X-ray source that appears to emanate from a compact star cluster in NGC 6099, a vast elliptical galaxy located about 450 million light-years from Earth.

    The Hubble Space Telescope has played a crucial role in the study of supermassive black holes. Shortly after the telescope launched into space in 1990, it “discovered that throughout the Universe can contain supermassive black holes at their centers weighing millions or billions of times the mass of our Sun,” NASA explains. However, Hubble also found that galaxies can have millions of much smaller black holes that weigh less than 100 times the mass of the Sun. These relatively tiny black holes are born when especially massive stars die.

    Two bright elliptical galaxies and several stars appear in a dark sky. A label points to a faint object marked "HLX-1" near the lower edge of the image.
    ‘A Hubble Space Telescope image of a pair of galaxies: NGC 6099 (lower left) and NGC 6098 (upper right). The white dot labeled HLX-1 is the visible-light component of the location of a compact star cluster where an intermediate-mass black hole is tearing apart a star.’ | Credit: Science: NASA, ESA, Yi-Chi Chang (National Tsing Hua University); Image Processing: Joseph DePasquale (STScI)

    However, while supermassive black holes can be found throughout the cosmos, and scientists can observe small black holes, there is a third class of black holes that has proven much more elusive: intermediate-mass black holes (IMBHs).

    In true Goldilocks fashion — not too big and not too small — these IMBHs are often invisible to astronomers because they do not “gobble as much gas and stars” as supermassive black holes, which creates powerful, detectable radiation.

    Image of galaxy NGC 6099 showing two large glowing galaxies, several bright stars, and faint galaxies. Colored text labels imaging filters. A scale bar shows 33,000 light-years. Compass indicates north and east directions.
    ‘This compass image of Hubble and Chandra data shows two elliptical galaxies, NGC 6098 at upper right and NGC 6099 at lower left. The fuzzy purple blob at bottom center depicts X-ray emission from a compact star cluster. The X-rays are produced by an intermediate-mass black hole tearing apart a star. Wavelength information at the top left corner shows the components of the image. A scale bar appears at the bottom left corner and compass directional arrows at bottom right orient the viewer.’ | Credit: Science: NASA, ESA, CXC, Yi-Chi Chang (National Tsing Hua University); Image Processing: Joseph DePasquale (STScI)

    Instead, much like other transient cosmic events, IMBHs can only be observed when they happen to be detected while they are actively consuming a star.

    “When [IMBHs] occasionally devour a hapless bypassing star — in what astronomers call a tidal disruption event — they pour out a gusher of radiation,” NASA writes.

    The latest “probable” IMBH, NGC 6099 HLX-1, was “caught snacking” in telescope data about 40,000 light-years from NGC 6099’s galactic center. In the associated research, newly published in The Astrophysical Journal, scientists Yi-Chi Chang, Roberto Soria, Albert K.H. Kong, Alister W. Graham, Kirill A. Grishin, and Igor V. Chilingarian explain how they initially discovered unusual X-rays in Chandra observations from 2009. The team then followed up using the European Space Agency’s (ESA) XMM-Newton space observatory.

    “X-ray sources with such extreme luminosity are rare outside galaxy nuclei and can serve as a key probe for identifying elusive IMBHs. They represent a crucial missing link in black hole evolution between stellar mass and supermassive black holes,” says the lead author of the research, Yi-Chi Chang of the National Tsing Hua University, Hsinchu, Taiwan.

    The X-ray emissions from NGC 6099 HLX-1 were three million degrees, which is consistent with expected observations of a tidal disruption event. Hubble data revealed evidence that a small cluster of stars was located around the suspected IMBH, which would provide ample sustenance for the medium-sized black hole. The stars are incredibly close together, separated by only a few light-months, or about 500 billion miles.

    The suspected IMBH hit its maximum observed brightness in 2012 and declined in intensity until 2023.

    “If the IMBH is eating a star, how long does it take to swallow the star’s gas? In 2009, HLX-1 was fairly bright. Then in 2012, it was about 100 times brighter. And then it went down again,” explains study co-author Roberto Soria of the Italian National Institute for Astrophysics (INAF). “So now we need to wait and see if it’s flaring multiple times, or there was a beginning, there was peak, and now it’s just going to go down all the way until it disappears.”

    NGC 6099 HLX-1 remains a fascinating area of study because scientists believe intermediate-mass black holes may continue growing and someday become supermassive black holes through coalescence with other IMBHs that may be orbiting a galaxy’s center, like satellite black holes.

    An alternative theory is that supermassive black holes in galaxies formed from dark-matter halos in the early Universe, rather than being born from multiple black holes combining or through ongoing mass accumulation.

    “So if we are lucky, we’re going to find more free-floating black holes suddenly becoming X-ray bright because of a tidal disruption event. If we can do a statistical study, this will tell us how many of these IMBHs there are, how often they disrupt a star, how bigger galaxies have grown by assembling smaller galaxies.” Soria adds.

    However, the studies are complicated by the fact that space telescopes, especially ones like Chandra and XMM-Newton that only look at a very small portion of the sky at a time, very rarely discover tidal disruption events. The Vera C. Rubin Observatory, newly opened in Chile, looks at a huge portion of the sky each night and could help locate tidal disruption events for further study, albeit in optical light.


    Image credits: Science: NASA, ESA, CXC, Yi-Chi Chang (National Tsing Hua University); Image Processing: Joseph DePasquale (STScI)

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