Academia Sinica researchers said they have calculated that a supermassive black hole in a galaxy 4 billion light-years away might contain more than 300 million times the Sun’s mass by analyzing images taken by radio telescopes, adding that the findings are key to understanding the formation and evolution of black holes and their host galaxies.
A team led by research fellows Kenneth Wong (黃活生), Sherry Suyu (蘇游瑄) and Satoki Matsushita on Monday said that it analyzed the high-resolution images of SDP.81, a galaxy located 4 billion light-years from Earth, taken by the Atacama Large Millimeter Array (ALMA) in Chile — the biggest radio telescope array in the world for observing radiation from the early universe, molecular gas and interstellar dust.
The images were taken during a chance alignment of the Earth, SDP.81 and another galaxy — all located in a straight line spanning 12 billion light-years, Wong said.
The images display what is known as the Einstein ring: the deformation of light from a source — in this case, the background galaxy 12 billion light-years away — into a ring due to gravitational lensing by an object with an extremely large mass — SDP.81, Wong said.
The gravity of the massive foreground galaxy deflects the light from the background galaxy and creates the ring structure, allowing the team to calculate the mass of a supermassive black hole, located near the center of SDP.81, by analyzing the brightness of the ring and of the central image within the ring, Wong said, adding that the Hubble Space Telescope is unable to capture such images as it only detects visible and infrared light.
“This is the highest resolution image of a gravitational lens that has ever been taken, and the amount of detail in this image is much greater than even space-based telescope observations,” he said.
Almost all massive galaxies seem to have supermassive black holes at their centers. Previously, scientists could only directly calculate the mass for galaxies immediately adjacent, Wong said.
“ALMA now gives us the sensitivity to look at the central image of the lens, which can allow us to determine the mass of much more distant black holes,” Wong said.
Measuring the masses of more distant black holes is critical to understanding their relationship with their host galaxies and how they grow over time, he added.
The research was published last month in the peer-reviewed Astrophysical Journal periodical.
Next year the team plans to observe a gravitational lens located 6 billion light-years away.
CAUTION: Based on intelligence from the nation’s security agencies, MOFA has cautioned Taiwanese travelers about heightened safety risks in China-friendly countries The Ministry of Foreign Affairs (MOFA) yesterday urged Taiwanese to be aware of their safety when traveling abroad, especially in countries that are friendly to China. China in June last year issued 22 guidelines that allow its courts to try in absentia and sentence to death so-called “diehard” Taiwanese independence activists, even though Chinese courts have no jurisdiction in Taiwan. Late last month, a senior Chinese official gave closed-door instructions to state security units to implement the guidelines in countries friendly to China, a government memo and a senior Taiwan security official said, based on information gathered by Taiwan’s intelligence agency. The
The National Immigration Agency (NIA) said yesterday that it will revoke the dependent-based residence permit of a Chinese social media influencer who reportedly “openly advocated for [China’s] unification through military force” with Taiwan. The Chinese national, identified by her surname Liu (劉), will have her residence permit revoked in accordance with Article 14 of the “Measures for the permission of family- based residence, long-term residence and settlement of people from the Mainland Area in the Taiwan Area,” the NIA said in a news release. The agency explained it received reports that Liu made “unifying Taiwan through military force” statements on her online
Taiwan Semiconductor Manufacturing Co (TSMC), the world’s largest contract chipmaker, said yesterday that it is looking to hire 8,000 people this year, at a time when the tech giant is expanding production capacity to maintain its lead over competitors. To attract talent, TSMC would launch a large-scale recruitment campaign on campuses across Taiwan, where a newly recruited engineer with a master’s degree could expect to receive an average salary of NT$2.2 million (US$60,912), which is much higher than the 2023 national average of NT$709,000 for those in the same category, according to government statistics. TSMC, which accounted for more than 60 percent
Tung Tzu-hsien (童子賢), a Taiwanese businessman and deputy convener of the nation’s National Climate Change Committee, said yesterday that “electrical power is national power” and nuclear energy is “very important to Taiwan.” Tung made the remarks, suggesting that his views do not align with the country’s current official policy of phasing out nuclear energy, at a forum organized by the Taiwan People’s Party titled “Challenges and Prospects of Taiwan’s AI Industry and Energy Policy.” “Taiwan is currently pursuing industries with high added- value and is developing vigorously, and this all requires electricity,” said the chairman
RSS