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Scientists have proposed a new method for finding tightly bound supermassive black hole pairs by searching for stars that flash repeatedly as their light is magnified by the black holes’ gravity。 The timing and brightness of these bursts could provide a unique fingerprint of black holes slowly spiraling toward a future collision
Abstract We present the first Event Horizon Telescope (EHT) observations of Sagittarius A* (Sgr A*), the Galactic center source associated with a supermassive black hole. These observations were conducted in 2017 using a global interferometric array of eight telescopes operating at a wavelength of λ = 1.3 mm. The EHT data resolve a compact emission region with intrahour variability. A variety of imaging and modeling analyses all support an image that is dominated by a bright, thick ring with a diameter of 51.8 ± 2.3 μ as (68% credible interval). The ring has modest azimuthal brightness asymmetry and a comparatively dim interior. Using a large suite of numerical simulations, we demonstrate that the EHT images of Sgr A* are consistent with the expected appearance of a Kerr black hole with mass ∼4 × 10 6 M ⊙ , which is inferred to exist at this location based on previous infrared observations of individual stellar orbits, as well as maser proper-motion studies. Our model comparisons disfavor scenarios where the black hole is viewed at high inclination ( i > 50°), as well as nonspinning black holes and those with retrograde accretion disks. Our results provide direct evidence for the presence of a supermassive black hole at the center of the Milky Way, and for the first time we connect the predictions from dynamical measurements of stellar orbits on scales of 10 3 –10 5 gravitational radii to event-horizon-scale images and variability. Furthermore, a comparison with the EHT results for the supermassive black hole M87* shows consistency with the predictions of general relativity spanning over three orders of magnitude in central mass.
Abstract When surrounded by a transparent emission region, black holes are expected to reveal a dark shadow caused by gravitational light bending and photon capture at the event horizon. To image and study this phenomenon, we have assembled the Event Horizon Telescope, a global very long baseline interferometry array observing at a wavelength of 1.3 mm. This allows us to reconstruct event-horizon-scale images of the supermassive black hole candidate in the center of the giant elliptical galaxy M87. We have resolved the central compact radio source as an asymmetric bright emission ring with a diameter of 42 ± 3 μ as, which is circular and encompasses a central depression in brightness with a flux ratio ≳10:1. The emission ring is recovered using different calibration and imaging schemes, with its diameter and width remaining stable over four different observations carried out in different days. Overall, the observed image is consistent with expectations for the shadow of a Kerr black hole as predicted by general relativity. The asymmetry in brightness in the ring can be explained in terms of relativistic beaming of the emission from a plasma rotating close to the speed of light around a black hole. We compare our images to an extensive library of ray-traced general-relativistic magnetohydrodynamic simulations of black holes and derive a central mass of M = (6.5 ± 0.7) × 10 9 M ⊙ . Our radio-wave observations thus provide powerful evidence for the presence of supermassive black holes in centers of galaxies and as the central engines of active galactic nuclei. They also present a new tool to explore gravity in its most extreme limit and on a mass scale that was so far not accessible.
A stunning spiral galaxy called Messier 88 is racing through the crowded Virgo Cluster on a journey that will dramatically reshape its future。 At its heart lies a supermassive black hole about 100 million times the mass of the Sun, while its graceful spiral arms sparkle with young star clusters and dark clouds of dust。 But as M88 plunges deeper int
NASA expects to begin stacking the SLS rocket this summer for next year's Artemis III launch
Scientists at the University of Houston have shattered a long-standing superconductivity record, creating a material that can conduct electricity with zero resistance at the highest temperature ever achieved under normal pressure conditions。 Their breakthrough pushes superconductivity to 151 Kelvin (minus 122°C), beating a record that stood for mor
Scientists working at CERN’s Large Hadron Collider may be seeing the strongest hints yet of physics beyond the Standard Model — the decades-old theory that explains the fundamental particles and forces of the universe。 By studying incredibly rare particle transformations called “penguin decays,” researchers found behavior that doesn’t fully match t
Researchers at EPFL have developed a chip-scale ultrafast laser that performs on par with traditional tabletop femtosecond lasers。 The innovation could make advanced laser technologies far smaller, cheaper, and more accessible for applications ranging from medical diagnostics to atomic clocks
A breakthrough hydrogen-production method could make clean fuel far cheaper and easier to generate。 Researchers at the University of Birmingham developed a perovskite-based catalyst that splits water into hydrogen at much lower temperatures than existing technologies, potentially allowing factories, steel plants, cement works, and renewable energy
A decades-old mystery about Saturn has finally been solved thanks to the James Webb Space Telescope。 Scientists discovered that Saturn’s changing “rotation rate” was never caused by the planet speeding up or slowing down, but by powerful winds high in its atmosphere。 Webb’s unprecedented observations revealed that Saturn’s northern lights actively
SpaceX won’t get easy access to billions of dollars from passive investors
Scientists have uncovered unexpected quantum complexity inside cobalt, a metal long thought to be fully understood。 Advanced measurements revealed a dense network of topological electronic states that remain robust at room temperature。 These states enable extremely fast electron behavior and can be switched or controlled using magnetism
In the end, the three companies involved all point the finger at each other
“Why don’t we just frickin’ call Apple
Seller of the Sound Blaster Katana V2X doesn't consider the behavior a vulnerability
A remarkable crystal called molybdenum oxychloride could help make futuristic technologies like smart contact lenses and ultrathin AR glasses a reality。 Scientists have created the first detailed experimental map of its optical properties, revealing the strongest light-bending effect ever measured in a natural material。 The crystal can act either l
A giant planet nearly 700 light-years away has a bizarre daily weather cycle where mineral clouds appear every morning and vanish by nightfall。 Using the James Webb Space Telescope, astronomers discovered that WASP-94A b’s mornings are filled with clouds made of rock-like minerals, while its evenings are surprisingly clear。 The finding gave scienti
NASA’s futuristic X-59 jet is about to face its biggest challenge yet: breaking the sound barrier for the first time。 After a successful series of test flights that pushed the aircraft to near-supersonic speeds, engineers are preparing to fly it faster than Mach 1 and eventually up to Mach 1。6 at 60,000 feet
Developer felt "beaten up," with "no choice" but to shrink data center
Musk can't be trusted to protect X user privacy, public commenters warn FTC