File:Multiwavelength View of Sagittarius A* (51657196986).jpg

An enormous swirling vortex of hot gas glows with infrared light, marking the approximate location of the supermassive black hole at the heart of our Milky Way galaxy. This multiwavelength composite image includes near-infrared light captured by NASA’s Hubble Space Telescope, and was the sharpest infrared image ever made of the galactic center region when it was released in 2009. Dynamic flickering flares in the region immediately surrounding the black hole, named Sagittarius A*, have complicated the efforts of the Event Horizon Telescope (EHT) collaboration to create a closer, more detailed image. While the black hole itself does not emit light and so cannot be detected by a telescope, the EHT team is working to capture it by getting a clear image of the hot glowing gas and dust directly surrounding it.

NASA’s upcoming James Webb Space Telescope, scheduled to launch in December 2021, will combine Hubble’s resolution with even more infrared light detection. In its first year of science operations, Webb will join with EHT in observing Sagittarius A*, lending its infrared data for comparison to EHT’s radio data, making it easier to determine when bright flares are present, producing a sharper overall image of the region.

In the composite image shown here, colors represent different wavelengths of light. Hubble’s near-infrared observations are shown in yellow, revealing hundreds of thousands of stars, stellar nurseries, and heated gas. The deeper infrared observations of NASA’s Spitzer Space Telescope are shown in red, revealing even more stars and gas clouds. Light detected by NASA’s Chandra X-ray Observatory is shown in blue and violet, indicating where gas is heated to millions of degrees by stellar explosions and by outflows from the supermassive black hole.