Fastest Star S301 Poised to Unravel Black Hole's Spin, Test Einstein's Theory

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Astronomers have just unveiled the fastest star ever recorded in our Milky Way galaxy, named S301, and it's set to revolutionize our understanding of black holes and Einstein's theory of General Relativity. Discovered by the GRAVITY+ collaboration, this star orbit the Milky Way supermassive black hole, Sagittarius A, on an incredibly tight 8.7-year path, reaching speeds of 25,000 kilometers per second – more than 8% the speed of light. Its extreme proximity and speed make it an unprecedented cosmic laboratory for testing fundamental physics. What makes S301 so special is its unique dance with the gravitational behemoth at our galaxy's heart. Its orbit is so close to Sagittarius A that it will allow scientists to directly measure the black hole's spin, a characteristic that has long eluded direct observation. This measurement hinges on detecting the Lense-Thirring effect, also known as frame-dragging, where the spinning black hole actually twists the fabric of spacetime around it, subtly altering the star's path. Previous S-stars, like S2, have helped confirm gravitational redshift and Schwarzschild precession, but S301 tighter orbit offers a much more sensitive probe for this crucial aspect of General Relativity. Researchers, including Nobel Prize winner Reinhard Genzel and MPE PhD student Felix Mang, expect that within the next decade or so, tracking S301 precise orbit will provide enough data to accurately determine Sagittarius A* spin. This groundbreaking observation promises to open a new window into the properties of spacetime in extreme black-hole environments and offer fresh insights into how these colossal objects grow and influence their galactic surroundings. The findings are expected to be published in Nature.