Produced by the Event Horizon Telescope (EHT) Collaboration, the image is direct visual evidence of the existence of the supermassive black hole in the heart of the Milky Way. The first image of Sagittarius A* was revealed at a press conference held on May 12, 2022. Brown in 1982 because the source was considered “exciting.” It is a reference to the naming system for excited state atoms, which are given an asterisk to denote their excited state.īrown and his team had obtained a high-resolution map of the Galactic centre using the Very Large Array (VLA) and understood that the strongest radio emission from the Galactic centre was coming from a compact nonthermal radio object. The asterisk (*), pronounced “star,” was added by Robert L. The letter A denoted the brightest radio source in Sagittarius, the Archer. Kraus, Hsien-Ching Ko, and Sean Matt (Ohio State University), who listed all the radio sources they detected in the sky and arranged them by constellation in 1954. The name Sagittarius A was given to the radio source by John D. Some of the material falls toward the black hole, but some of it is directed away from it, keeping emissions low.Ģ6,673 ± 42 light-years (8,178 ± 13 parsecs) They revealed that magnetic fields cause the ring of dust and gas around Sgr A* to flow into an orbit around the black hole. In 2019, observations with NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA) provided a possible explanation for the relatively low emissions coming from Sgr A*. With a bolometric luminosity only about 100 times that of the Sun, it would be difficult to detect if not for its proximity. The black hole is notable for its weak emission. ![]() ![]() This is less than the distance between Mercury and the Sun at the planet’s closest approach (46 million km). It has a mass of 4.154 million Suns packed within a diameter of 51.8 million kilometres (32.2 million miles). Sagittarius A* is the Milky Way’s central supermassive black hole. Credit: EHT Collaboration Sagittarius A* (Sagittarius A-star) The image of the Sgr A* black hole is an average of the different images the EHT Collaboration has extracted from its 2017 observations. The new view captures light bent by the powerful gravity of the black hole, which is four million times more massive than our Sun. Although we cannot see the event horizon itself, because it cannot emit light, glowing gas orbiting around the black hole reveals a telltale signature: a dark central region (called a shadow) surrounded by a bright ring-like structure. The telescope is named after the event horizon, the boundary of the black hole beyond which no light can escape. It was captured by the Event Horizon Telescope (EHT), an array which linked together eight existing radio observatories across the planet to form a single “Earth-sized” virtual telescope. It’s the first direct visual evidence of the presence of this black hole. This is the first image of Sgr A*, the supermassive black hole at the centre of our galaxy. The first black hole to be imaged lies at the centre of the galaxy Messier 87, one of the brightest members of the Virgo Cluster. It was the second image of a galactic black hole to be produced. The first image of the black hole at the center of the Milky Way Galaxy was released in May 2022. The radio and infrared emissions from Sgr A come from dust and gas being heated to millions of degrees as they fall into the central black hole. The Galactic centre is best observed in the infrared and radio bands. The source is hidden from view by large dust clouds in the Milky Way’s spiral arms. ![]() Sagittarius A cannot be seen in optical wavelengths because of the effect of 25 magnitudes of extinction. The Milky Way’s central black hole lies at a distance of 26,673 ± 42 light years from Earth in the direction of Sagittarius constellation, near the border with Scorpius. Sagittarius A* (pronounced “Sagittarius A-star”) is the supermassive black hole at the centre of our galaxy. The radio source consists of the supernova remnant Sagittarius A East, the spiral structure Sagittarius A West, and the bright compact radio source at the centre of the spiral structure, called Sagittarius A*. Sagittarius A (Sgr A) is a complex radio source located at the centre of the Milky Way Galaxy.
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