Astronomers have unveiled the first image of the supermassive black hole at the center of our own Milky Way galaxy. This result provides overwhelming evidence that the object is indeed a black hole and yields valuable clues about the workings of such giants, which are thought to reside at the center of most galaxies.
The image was produced by a global research team called the Event Horizon Telescope (EHT) collaboration, using observations from a worldwide network of radio telescopes.
Michael Nowak, research professor of physics in Arts & Sciences at Washington University in St. Louis, is part of the EHT collaboration. Nowak researches high-energy phenomena related to the physics of black holes. His areas of research interest include stellar mass black holes in our galaxy; supermassive black holes in the centers of our and other galaxies; and neutron stars.
“We’ve been studying this object – known as Sagittarius A* – over a broad range of energies ranging from radio all the way through X-rays and gamma rays for nearly two decades now, trying to understand how it can change from a seemingly ‘quiet’ black hole to having dramatic outbursts that last minutes to hours,” said Nowak, who is a faculty fellow of the university’s McDonnell Center for the Space Sciences. “This variability has made observations with the Event Horizon Telescope – which themselves usually last hours – really tricky to perform and analyze. The EHT team has done a really impressive job of meeting this challenge.
“These new observations are helping us to understand the connection between the black hole at the center of our galaxy and the emission surrounding it,” he said. “It’s one more piece in the puzzle of trying to understand concepts like how black holes can form jets, which can have a dramatic impact on their surrounding environment.”