“Over 10 years ago, we linked radio dishes in California and Arizona to the SMA and other telescopes in Hawaii, allowing us to discover features in Sgr A* that were the size of the black hole shadow,” said Sheperd “Shep” Doeleman, founding director of the EHT. Together, the telescopes observed Sgr A* on multiple nights in 2017, collecting data for many hours in a row, similar to using a long exposure time on a camera. To image it, the team created the powerful EHT, which linked together eight existing radio observatories across the planet to form a single “Earth-sized” virtual telescope.īased on the summit of Maunakea in Hawaii, the Submillimeter Array (SMA), a joint operation between the CfA and Academia Sinica Institute of Astronomy and Astrophysics (ASIAA), was one of the eight instrumental telescopes utilized to capture the image. Sgr A* is about 27,000 light-years away, appearing to those on Earth to have the same size in the sky as a donut on the moon. "This image confirms decades of theoretical work to understand how black holes eat." "We now see that the black hole is swallowing the nearby gas and light, pulling them into a bottomless pit," said Ramesh Narayan, a theoretical astrophysicist at the CfA. This new view shows light bent by the powerful gravity of the black hole, which is 4 million times more massive than the sun. The black hole itself is completely dark, yet glowing gas around it reveals a tell-tale signature: a dark central region, called a shadow, surrounded by a bright ring-like structure. At this close range, the black hole accelerates matter to close to the speed of light and bends the paths of photons in the warped spacetime.” “With the EHT image, we have zoomed in a thousand times closer than these orbits, where the gravity grows a million times stronger. “For decades, astronomers have wondered what lies at the heart of our galaxy, pulling stars into tight orbits through its immense gravity," said CfA astrophysicist Michael Johnson. This strongly suggested that the object-known as Sagittarius A*, or Sgr A*-was a black hole today’s image provides the first direct visual evidence of it. Scientists had previously seen stars orbiting around something invisible, compact and very massive in the galaxy’s core. The image, described today in a special issue of The Astrophysical Journal Letters, is a long-anticipated look at the massive object that sits at the very center of the Milky Way. The image was produced by a global research team called the Event Horizon Telescope (EHT), which includes scientists from the Center for Astrophysics | Harvard & Smithsonian (CfA), using observations from a worldwide network of radio telescopes. The result provides overwhelming evidence that the object at the heart of the galaxy is indeed a black hole, and it yields valuable clues about the workings of such giants, which are thought to reside at the center of most galaxies. Eliot Elisofon Photographic Archives, African ArtĪstronomers unveiled the first image of the supermassive black hole at the center of the Milky Way galaxy in simultaneous press conferences around the world today, May 12.
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