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A privately operated spacecraft that was intended to rescue NASA’s aging Swift Observatory succeeded in approaching the troubled telescope and photographing it, even though the rescue mission had been abandoned two weeks earlier. However, the robotic spacecraft, equipped with three mechanical arms, was forced to retreat because it was running low on fuel, according to Katalyst Space Technologies, the company behind the attempted rescue. “We got so close, but so far,” Katalyst CEO Ghonhee Lee told The Associated Press this week. Katalyst’s Link spacecraft came within about 15 kilometers (9 miles) of Swift on Tuesday. During the approach, its instruments collected valuable information about the aging observatory for NASA. Although the rescue attempt had been officially canceled in August because of problems with Link, Katalyst decided to continue the approach as a training exercise for future satellite-maintenance missions. Shortly after being launched toward Swift in July, Link began spinning uncontrollably. Mission controllers eventually managed to reduce the spacecraft’s rotation and regain control, but doing so consumed a significant amount of its limited fuel. As a result, Link no longer had enough fuel to move Swift into a higher and more stable orbit that would have allowed the telescope to continue its scientific work. Lee attributed Link’s difficulties partly to the speed with which the mission had to be developed. The spacecraft was prepared in only nine months, forcing engineers to use available components rather than wait for their preferred equipment. NASA spent $30 million on the rescue attempt, which was designed from the beginning as a fast-paced experimental mission. Both NASA and Katalyst regarded it as an opportunity to test new technology, although they were concerned that a collision could create dangerous clouds of space debris. NASA Administrator Jared Isaacman said after Sunday's launch of the Roman Space Telescope that the unsuccessful result was disappointing but still provided valuable experience. He argued that NASA should continue pursuing challenging missions because lessons learned from failures can improve future efforts. Isaacman also said extending the operational life of expensive spacecraft is worthwhile when doing so costs less than building replacements. The Roman Space Telescope, for example, was designed to be refueled despite being intended to operate roughly 1 million miles (1.6 million kilometers) from Earth. Lee said Link probably does not have enough fuel for another attempt to approach Swift closely. Nevertheless, the spacecraft can continue testing its three approximately 3-foot (1-meter) robotic arms and gathering useful information before it eventually falls back into Earth's atmosphere and burns up within the coming weeks. Swift was launched in 2004 and still has some time left in orbit, although its remaining lifetime depends partly on solar activity. Strong solar storms in recent years have caused its orbit to decay much faster than anticipated. By Friday, Swift was orbiting about 208 miles (335 kilometers) above Earth, less than half the altitude at which it began studying some of the universe's most powerful explosions. NASA expects Swift to reenter the atmosphere sometime between October and the end of the year. The agency restarted observations with the telescope last week after suspending them earlier this year to preserve its limited power supply. Solar activity has also caused the orbit of the Hubble Space Telescope to gradually decline. Katalyst is working on a newer spacecraft that could eventually raise Hubble into a higher and more durable orbit. Lee noted that Hubble is still expected to remain operational for several more years, meaning that any potential servicing mission is not an immediate necessity. According to Lee, repairing and maintaining aging telescopes and other satellites was once considered a highly specialized idea. He believes, however, that such missions will become increasingly common as space agencies and companies look for ways to extend the useful lives of valuable spacecraft. The report was later corrected to clarify that Link's close approach to Swift occurred on Tuesday rather than the previous weekend, following updated information provided by Katalyst Space Technologies.

Digital technology, artificial intelligence and smart agricultural machinery are transforming farming across northeast China's Heilongjiang Province, one of the country's most important grain-producing regions. For 16 consecutive years, Heilongjiang has ranked first in China in total grain production. Its farming sector is already highly mechanized, with the mechanization rate for plowing, planting and harvesting reaching 99.28 percent. Now, the province is moving toward smarter farming, using AI, drones, remote sensing and advanced machinery to help farmers monitor crops, improve efficiency and make more informed decisions. The shift is part of China's broader efforts to strengthen food security and modernize rural areas. Digital technology changes farming At Beidahuang Information Company in Harbin, a large digital map tracks around 48 million mu, or about 3.2 million hectares, of farmland. The system receives real-time information on soil conditions, crop growth and agricultural machinery. Satellite technology, the Internet of Things and AI are increasingly being used throughout the farming process, from planting to harvesting. Wang Hao, deputy general manager of the company's market operation center, said technology has made it possible to monitor much larger areas in less time. Previously, a farmer could inspect about 200 mu of farmland in a day on foot. With drones and remote sensing, crop conditions across vast areas can now be updated every five days, he said. The data helps farmers make decisions on fertilization, pest control and other farm activities. The company has developed more than 60 digital systems for agricultural management. Its AI model for cold-region crops uses information on soil, weather and crop growth to help create planting plans and recommend appropriate fertilizer use. The company's agricultural service app has also helped improve efficiency and reduce management costs, with online transactions through the platform exceeding 100 billion yuan, or about $14.74 billion. However, Wang said large-scale adoption of smart agriculture still faces challenges, including limited data, differences in local farming conditions and the need to test AI systems in different environments. Smart machines enter the fields Smart agricultural equipment is also becoming increasingly common in Heilongjiang. At one farming base, a four-wheel laser weeding robot moves through crop rows using cameras and sensors to identify weeds. The system then uses lasers to remove the unwanted plants without damaging crops. Li Yongwei, deputy general manager of Harbin Huagong Zhiyun Technology Co., Ltd., said traditional weeding often depends on manual labor or chemicals, both of which can be costly or harmful to the environment. He said the laser technology can remove more than 95 percent of weeds while keeping crop damage below 0.1 percent. It can also reduce weeding costs by up to 70 percent compared with manual work. Agricultural machinery is also becoming more advanced. At Heilongjiang Dewo Technology Development Co., Ltd., electric-drive precision seeders allow farmers to monitor and adjust air pressure and seed spacing in real time through smart terminals. According to the company, the machines can operate about 50 percent faster than traditional mechanical seeders while reducing seed damage. Dewo now accounts for more than 60 percent of China's high-end electric-drive seeder market and has begun exporting its equipment overseas. The company has supplied potato farming machinery to countries including Russia, Kazakhstan, Peru and Zimbabwe, while also exporting seeders to the Republic of Korea. Push for intelligent farming Heilongjiang recorded its 22nd consecutive bumper harvest in 2025, producing a record 82 million tonnes of grain. The province also had around 676,000 intelligent agricultural machines, the highest number in China. The provincial government plans to further expand the use of agricultural robots, smart farming equipment and other advanced technologies during China's 15th Five-Year Plan period from 2026 to 2030. Construction also began in August on a national pilot base for AI applications in crop farming, aimed at solving technological challenges and developing AI systems that can be used on a larger scale. The move reflects China's wider push to modernize agriculture through better farmland, improved seeds, advanced machinery and new farming methods. China is also expanding the use of drones, IoT technology and robots in rural areas as part of efforts to improve agricultural productivity and support rural development. Hu Jinyou, a professor at China Agricultural University, said relying only on manual labor and traditional farming methods is no longer practical. Although smart agriculture still needs further improvement, he said the deeper integration of AI and farming is an irreversible trend, with a new generation of educated farmers expected to make digital farm management increasingly common.

Simple practices such as mindfulness, gratitude journaling and optimism training may help improve heart health within a few weeks, according to a new review of clinical studies. The research found that positive psychology and mindfulness-based programmes were linked to improvements in blood pressure, inflammation and other risk factors for heart disease. The review, led by Rosalba “Rose” Hernandez, a professor at the University of Illinois Urbana-Champaign, examined 18 randomized controlled trials involving people with existing cardiovascular risks, including high blood pressure, heart failure and other health conditions. Most programmes lasted between six and 12 weeks and included weekly sessions along with activities participants practised at home. The interventions were delivered through phone calls, apps, text messages, journaling, group sessions and a combination of in-person and online support. Hernandez said mindfulness-based programmes lasting eight weeks showed improvements in systolic blood pressure and inflammatory markers among people with hypertension and those recovering from acute coronary syndrome. One 12-week digital programme based on spirituality produced one of the largest reductions in blood pressure, lowering systolic blood pressure by 7.6 points, according to the study. The researchers found that programmes involving frequent contact and regular practice were more consistently linked to improvements in heart health. “The therapeutic dose that was most consistently linked with improvements in blood pressure, inflammation and endothelial function was daily practice reinforced by weekly sessions over eight to 12-week periods,” Hernandez said. Some programmes also encouraged participants to adopt healthier lifestyles. An eight-week WhatsApp-based programme, which combined weekly sessions with daily tasks, encouraged people to exercise more, improve their diets and take medicines as prescribed. Another programme using motivational interviewing increased physical activity among heart patients by around 1,800 steps a day and also improved medication adherence. The researchers said mindfulness and positive psychology interventions could become useful additions to long-term heart disease prevention and treatment. However, continued, less intensive support may be needed to help people maintain healthier habits over time. The study, published in the journal Cardiology Clinics, adds to growing evidence suggesting that psychological well-being may play an important role in cardiovascular health. Researchers said optimism, gratitude and other positive emotional experiences have increasingly been linked to better heart health. An earlier study led by Hernandez also found that people with higher levels of optimism tended to have healthier hearts. The findings suggest that caring for mental and behavioural health could play an important role alongside conventional medical treatment in preventing heart disease and improving overall cardiovascular health. Source: Science Daily

Just off the coast of New York’s famous Hamptons beaches, marine researcher Greg Metzger reels in one of the day’s most impressive catches — a young but powerful sand tiger shark. Working quickly, Metzger and another researcher secure the sharp-toothed female shark alongside their boat. They collect tissue samples and attach small tracking devices before releasing it back into the ocean. Metzger said the shark’s tough skin was so strong that it could even damage a surgical-grade scalpel. “It’s no surprise that they’ve survived since prehistoric times and are still going strong,” he said. Metzger and other scientists are catching, tagging and releasing different species of sharks to better understand their populations and movements around Long Island. The research is also helping scientists learn more about one of the world’s few confirmed nurseries for great white sharks, where large numbers of young sharks spend their early years feeding and growing. Other recognised great white shark nursery areas are located off the coasts of California, Mexico and Australia. Metzger, who also teaches marine science at Southampton High School, said researchers hope their work will help change public perceptions of sharks. Many people fear sharks, but he said they are far more complex than the “mindless eating machines” often shown in popular culture. Tracking sharks across thousands of kilometresResearchers use different types of electronic tags to follow the sharks. Some send acoustic signals that can be detected by monitoring stations along the coast, while others record information such as water depth and temperature before eventually detaching from the animal. The tracking data shows that some sharks travel vast distances during the year. Bradley Peterson, a marine scientist at Stony Brook University, said sharks tagged near Long Island have later been detected in waters off North Carolina, Georgia, Florida and the Gulf of Mexico before returning north the following year. Many of them appear to travel to Long Island during the warmer months to feed and build up energy. Scientists are also seeing a wider variety of shark species in the area. Frank Quevedo, executive director of the South Fork Natural History Museum and Nature Center, said warmer coastal waters may be encouraging more species normally found farther south to move north during the summer. Researchers have recently observed more spinner sharks, blacktip sharks and bull sharks in the region. However, Metzger said sharks have always been present in Long Island waters. He believes people are simply seeing them more often because of modern technology, including drones and mobile phone cameras. The International Shark Attack File has no record of a fatal shark attack on Long Island, although several people have been bitten in recent years, including one incident this summer. Local authorities have introduced additional safety measures, including drones to spot sharks near beaches. Learning more about young great white sharksScientists are particularly interested in the young great white sharks that use the waters off Long Island as a nursery. According to Quevedo, newborn great whites can already measure about 4 feet (1.2 metres) and weigh up to 80 pounds (36 kilograms). Unlike many animals, they receive no care from their mothers and must survive on their own from birth. The relatively shallow coastal waters provide young sharks with a place to feed on schools of fish while avoiding larger predators, including adult sharks. As they grow, great white sharks move north in search of larger prey, particularly seals along the coast of Cape Cod in Massachusetts. But scientists have observed that warming waters may be encouraging young great whites to move into New England earlier than before, potentially bringing them closer to adult sharks. Research aims to support shark conservationScientists also hope the research will encourage greater efforts to protect sharks. Quevedo said the release of the novel and later film Jaws more than 50 years ago contributed to a rise in recreational shark fishing, including the hunting of great white sharks off the Hamptons. Because great white sharks do not begin reproducing until they are in their 20s or even later, killing younger sharks can have a serious impact on their populations. Conservation efforts in recent decades have helped some shark populations recover, although their numbers are still believed to be far below historical levels. Quevedo said sharks, particularly top predators, play an important role in maintaining healthy marine ecosystems. Protecting them, researchers say, is not only important for the survival of sharks but also for maintaining the balance of the ocean environment.

NASA’s newest space telescope blasted off Sunday on a mission to search for planets beyond our solar system, investigate the mysterious forces driving cosmic expansion and map the universe in unprecedented detail. SpaceX launched the $4.3 billion Nancy Grace Roman Space Telescope shortly after sunrise aboard a Falcon Heavy rocket from NASA’s Kennedy Space Center. The telescope is headed for an observation point about 1 million miles (1.6 million kilometres) from Earth, where NASA’s James Webb Space Telescope is also stationed. Named after Nancy Grace Roman, NASA’s first chief astronomer, the bus-sized observatory will take more than three months to reach its destination. Once operational, it is expected to provide the broadest view yet of the universe from space and survey vast regions at a speed unmatched by previous space telescopes. NASA science mission director Nicky Fox said Roman is expected to detect thousands of supernovae, tens of thousands of planets, billions of galaxies and tens of billions of stars. Its ability to observe an enormous area of the sky will allow scientists to investigate objects and phenomena that previous telescopes could not study as efficiently. Minutes after launch, the rocket’s two reusable side boosters returned to Cape Canaveral, landing vertically with loud sonic booms. Roman’s field of view is more than 100 times wider than that of the Hubble Space Telescope, which has been observing the universe for 36 years. The James Webb Space Telescope, meanwhile, offers a narrower but highly detailed view and can examine extremely distant objects dating back close to the beginning of the universe. Scientists expect the three NASA observatories, working alongside the European Space Agency’s Euclid spacecraft and the National Science Foundation’s Vera C. Rubin Observatory in Chile, to provide new insights into some of astronomy’s biggest unanswered questions. Roman will search across vast numbers of galaxies for stars that host planets. Once potentially interesting worlds are identified, Webb will be able to conduct more detailed observations of them. Senior project scientist Julie McEnery said Roman’s exceptionally wide reach would help scientists locate rare and unusual objects that are difficult to detect. One of the mission’s major goals is to investigate dark matter and dark energy, two poorly understood components believed to account for most of the universe. By mapping huge numbers of galaxies, scientists hope to better understand how the universe is expanding and the role played by these invisible forces. Speed is another major advantage of Roman. McEnery said observations that would take Hubble roughly a century to complete could be carried out by Roman in about a month. The telescope is expected to rapidly survey the dense central region of the Milky Way, offering scientists the deepest view yet of the galaxy’s heart. Roman will carry a wide-field infrared camera with sensitivity comparable to Hubble but capable of surveying the sky about 1,000 times faster. It will also feature an experimental coronagraph designed to block the light from stars, potentially allowing scientists to directly observe faint planets orbiting them. The telescope has also been designed with the possibility of future refuelling. If robotic servicing technology becomes available in the next decade, its operational life could potentially be extended. The launch came nearly a year earlier than originally scheduled and within budget. Roman is also the first NASA space telescope to be named after a woman. Retired NASA scientist Ed Weiler, who was hired by Roman in 1978, described the naming as long overdue. He helped popularise the term “Mother of Hubble” for Roman, who strongly advocated space-based observatories after joining the newly established NASA in 1959. Roman died in 2018 at the age of 93. Weiler said the mission was a fitting tribute to Roman and expressed confidence that she would have been proud to see the telescope bearing her name investigate questions such as the nature of dark energy. Hubble was launched in 1990 with a flawed primary mirror that later required astronauts to conduct repairs in space. Roman’s primary mirror, measuring nearly 8 feet (2.4 metres) across, is the same size as Hubble’s. The mirror was originally produced for a spy satellite programme. More than a decade ago, the US National Reconnaissance Office donated two surplus mirrors to NASA for potential scientific use. The second mirror remains in storage.

China has issued new ethical guidelines for the use of artificial intelligence in medical imaging research, aiming to ensure the safe and responsible development and clinical use of the technology. The Ministry of Science and Technology announced the guidelines on Friday. AI medical imaging uses artificial intelligence to analyse CT scans, MRI images and ultrasound results, helping doctors detect diseases and improve the speed and accuracy of diagnosis. However, the technology also involves large amounts of sensitive health information and raises concerns over privacy, data security, algorithmic bias and accountability. The new guidelines, issued by the medical ethics subcommittee of the national science and technology ethics committee, set out six key principles. These include promoting human welfare, ensuring fairness, respecting human autonomy, protecting privacy and data security, maintaining safety and control, and improving transparency. The guidelines said patients' health and interests must remain the top priority. Researchers will be required to obtain informed consent from people taking part in AI medical imaging research. Participants will also have the right to withdraw their consent at any time. The guidelines make clear that humans, not AI systems, will remain ultimately responsible for medical decisions. AI-generated results cannot be used as final diagnoses, while doctors will retain the final authority in making clinical decisions. The rules also ban exaggerated claims about the performance of AI models. Researchers and developers have also been urged to ensure fairness in AI systems and reduce the risk of biased diagnoses caused by unbalanced or limited training data. The guidelines are aimed at promoting the responsible use of AI in healthcare while ensuring that patient safety, privacy and human oversight remain central to the development of the technology.

Wildlife may be responding to the physical presence of people much more than scientists previously understood, according to a new study that tracked more than 4,500 animals across the United States. Researchers from the University of California, Santa Barbara, the Smithsonian’s National Zoo and Conservation Biology Institute, and Yale University combined GPS data from 37 animal species with anonymised cellphone location data. The study, published in the journal Science, found that animals respond differently to human activity depending on the species and how much the surrounding landscape has already been changed by people. The findings could help scientists develop more effective and species-specific approaches to wildlife conservation. “Humans have complicated effects on wildlife — from our physical presence to how we reshape habitats,” said Ruth Oliver, an assistant professor at UCSB’s Bren School of Environmental Science & Management and co-lead author of the study. The researchers took advantage of the COVID-19 lockdowns, when restrictions sharply changed people’s movements. This created a rare opportunity to examine the impact of human presence separately from long-term changes to the environment. The team studied weekly GPS records of 4,581 individual mammals and birds during comparable periods in 2019 and 2020. To measure human movement, researchers used anonymised cellphone location data with neighbourhood-level detail. They said this was the first time such data had been used to study how people’s physical presence affects animal movement. Scott Yanco, a research ecologist at the Smithsonian’s National Zoo and another co-lead author, said the cellphone data provided a rare opportunity to measure the direct effects of human presence on wildlife. The study found that 57% of the species examined were affected by both human presence and changes to the landscape. Human presence was linked to changes in the territory or environmental niche of 67% of mammal species and 68% of bird species. About 67% of mammal species and 41% of bird species reduced the amount of habitat they used when faced with a combination of human presence and landscape changes. Animals were particularly sensitive to people in areas with relatively little development, such as national parks, compared with heavily developed cities. However, wildlife did not respond in the same way. Wolves, for example, expanded their habitat use in response to human presence, possibly because they tend to move farther away from people or spread out to avoid human activity. White-tailed deer showed a different pattern. Their environmental niche expanded as landscapes became more developed but became smaller as human presence increased. Sandhill cranes showed the opposite response. Oliver said the findings highlight the importance of developing conservation measures for individual species because animals have different habitat needs, behaviours and threats. The research is part of the COVID-19 Bio-Logging Initiative, an international project that examined how wildlife responded to the sharp drop in human activity during pandemic lockdowns, a period researchers described as the “anthropause.” The wider initiative involved about 600 researchers and partners and collected around 1 billion location records from nearly 13,000 animals. The researchers said combining animal GPS tracking with human movement data can help distinguish between the effects of infrastructure and the effects of people simply being present. They are now investigating whether changes in animal behaviour caused by human activity and climate change help wildlife adapt or instead indicate stress that could increase their risk of death. Oliver said the findings offer hope that better policies could help humans and wildlife coexist by identifying where and when animals need more space. Source: Science Daily

The 2026 World Conference on Science Literacy will be held in Beijing from Sept. 19 to 21, during which the official establishment of the World Organization for Science Literacy will be announced, the China Association for Science and Technology (CAST) said Wednesday. At a press conference, CAST noted that September will once again serve as China's national science popularization month. The Beijing conference will bring together domestic and foreign experts and scholars to discuss solutions, strategies and pathways for enhancing public science literacy. Chinese humanoid robot maker Unitree surges 629% in market debut The World Organization for Science Literacy aims to build a global platform for shared discussion, joint development and mutual benefit in public science literacy efforts. It will also work to promote exchanges and cooperation, deepen collaborative innovation and foster a positive interaction between science, technology and society. Additionally, the body will strive to improve public science literacy to jointly address global challenges, contributing to global sustainable development and the building of a community with a shared future for mankind. The organization's member institutions include national academies of sciences, science and technology foundations, scientific societies and science museums. There are currently 32 founding members, including 20 overseas members from 19 countries across Asia, Europe, South America, Africa and Oceania. China launched its first national science popularization month in September 2025, following its revised Science and Technology Popularization Law which took effect Dec. 25, 2024, and designated September as the annual national science popularization month.

People who live to exceptionally old ages may have immune systems that continue adapting to new health threats, according to a new study. Researchers have found that supercentenarians — people aged 110 or older — have unusually high levels of specialised immune cells known as CD4 cytotoxic T lymphocytes (CD4 CTLs). These rare immune cells can kill certain tumour cells and multiply quickly when the body faces an infection. The findings, published August 19 in the Cell Press journal Cell Reports, suggest that this immune response may be linked to healthy ageing in people who reach extreme old age. “Immune ageing is not simply a process of decline,” said Kosuke Hashimoto, an associate professor at the University of Osaka in Japan and the study’s lead author. Killer T cells increase with age The researchers found that CD4 CTLs become more common as people reach very advanced ages. They examined blood samples from 28 people divided into three groups: those aged 70-99, 100-109 and 110 or older. The average share of CD4 CTLs increased from 4% among those aged 70-99 to 9.6% among people aged 100-109. It rose further to 17.6% among those aged 110 and above. The researchers said the increase may begin around the age of 100, although the pattern was not seen in every participant. One person under 100 had the highest level of CD4 CTLs recorded in the study. Large immune cell groups The team also examined T-cell receptors to understand why these cells become more common in some very old people. Their findings suggested that clonal expansion — when immune cells make large numbers of copies of themselves after detecting a threat — plays an important role. The largest single group of identical CD4 CTLs accounted for an average of 33.3% of all CD4 CTLs among the participants. In one centenarian, a single clone made up 53.8% of the person's CD4 CTLs. The researchers compared the receptor sequences of these dominant cells with those in a public database. They found nearly three dozen matches among people diagnosed with lung, breast and liver cancers. However, none of the centenarians or supercentenarians in the study had been diagnosed with those cancers. The researchers suggested that the increased immune cells may be responding to abnormal cells or possible cancer-related targets, although their exact targets are still unknown. Possible link to healthy ageing The study does not prove that high levels of CD4 CTLs protect people from cancer or directly help them live longer. The researchers only examined immune cells circulating in the blood and said more work is needed to understand their role in body tissues. Hashimoto said future research will focus on how these cells behave inside human tissues. “As we age, abnormal cells, including ageing and cancerous cells, become more common,” he said. “Our findings suggest that the immune system’s ability to adapt to these changes may contribute to exceptional longevity.” The study was supported by several Japanese research institutions and foundations, including the Japan Society for the Promotion of Science, the University of Osaka, the Takeda Science Foundation and the RIKEN Center for Integrative Medical Sciences. Source: Science Daily

Rapidly spinning stars may explain fading flares from black hole encountersUNB, New York: The rapid rotation of a star before its first close encounter with a black hole may explain why some recurring bursts of light from such encounters gradually become weaker, according to a new study by astrophysicists at Syracuse University. The study, published in The Astrophysical Journal, examines rare events known as repeating partial tidal disruption events (rpTDEs), in which a star survives a close encounter with a black hole but loses part of its mass. The surviving core remains in orbit and returns for further close encounters, shedding more material each time and producing fresh bursts of light. Astronomers have identified around 10 such repeating systems, four of which have shown progressively weaker flares. Previous theoretical models, however, struggled to explain the fading pattern. In a normal tidal disruption event, a black hole's powerful gravity completely tears a nearby star apart. The resulting debris falls toward the black hole and releases energy in the form of light. In a partial disruption, the star survives because it does not pass close enough to be completely destroyed. The amount of material stripped during each encounter depends partly on the star's internal structure. The researchers found that the star's rotation plays an important role. Previous work showed that the black hole's tidal forces can cause a surviving star to spin faster after each encounter. As the star spins faster, the material stripped from it can return to the black hole more quickly. This can keep the peak rate of material falling back relatively stable, even when the amount of stripped material declines, resulting in flares of similar brightness. The new study suggests that this changes if the star was already rotating rapidly before its first encounter. In that case, subsequent encounters cannot significantly increase its rotation rate. The stripped material therefore takes roughly the same amount of time to return to the black hole. As less material is removed during successive encounters, the peak fallback rate declines, causing each flare to become progressively fainter. The researchers believe the star's rapid initial rotation could be explained by the Hills mechanism, in which a binary star system is disrupted by a supermassive black hole. Under this scenario, two closely orbiting stars approach a black hole. The black hole's gravity tears the binary apart, sending one star away while capturing the other in a tight orbit. Before the disruption, the stars may have been tidally locked, meaning they rotated at the same rate as they orbited each other. A very close binary would therefore produce a rapidly spinning star, which could later be captured by the black hole. Lead researcher Ananya Bandopadhyay and her colleagues said the mechanism could explain both the star's rapid rotation and its unusually short orbit around the black hole. The findings may also shed light on some stars orbiting Sagittarius A*, the supermassive black hole at the centre of the Milky Way, where the Hills mechanism may have played a role in placing some stars into their current orbits.Source: Science Daily