A team of international scientists, including astronomers from the Center for Astrophysics | Harvard & Smithsonian (CfA), has made history by detecting a mid-infrared flare from the supermassive black hole at the center of the Milky Way galaxy. This detection marks the first-ever observation of this phenomenon using the James Webb Space Telescope.
The team observed Sgr A*, a massive black hole roughly 4 million times the mass of the Sun, and found that it exhibits flares in multiple wavelengths, including radio, near-infrared, and mid-infrared. These observations allowed scientists to better understand how the black hole emits flares and on what timescales they occur.
The mid-infrared flare is significant because it fills a gap in our understanding of the phenomenon. Infrared light has longer wavelengths than visible light but shorter wavelengths than radio light, making it ideal for observing objects that are difficult to detect at other wavelengths due to dust.
According to Joseph Michail, one of the lead authors on the paper, “Sgr A*’s flare evolves and changes quickly, in a matter of hours, and not all of these changes can be seen at every wavelength.” The team’s new observation in mid-infrared has helped fill this gap, providing valuable insights into the cause of flares.
The scientists used a combination of observations from the Submillimeter Array (SMA) and other facilities to detect the flare. The SMA detected a millimeter-wave flare lagging roughly 10 minutes behind the mid-infrared flare. This finding suggests that there may be a connection between the observed mm-variability and the observed MIR flare emission.
While the team’s findings support existing models of synchrotron emission from cooling electrons, they also highlight the need for further research into magnetic reconnection and turbulence in Sgr A*’s accretion disk. As Michail noted, “We still want to know, and need to find out… what other secrets is Sgr A* holding that the mid-IR can unlock?”
Source: https://www.cfa.harvard.edu/news/scientists-make-first-ever-detection-mid-ir-flares-sgr