Astronomers have achieved the highest resolution direct infrared images ever captured of a supermassive black hole using the Large Binocular Telescope Interferometer.
Supermassive black holes, known as active galactic nuclei (AGN), are located at the centers of particular galaxies. When matter is drawn into these black holes, it releases tremendous amounts of energy, making AGN some of the most powerful occurrences observable in the universe. Researchers at the University of Arizona have created the highest resolution direct infrared images of an AGN using the Large Binocular Telescope Interferometer.
Scientists from the Max Planck Institute for Astronomy in Germany also contributed to this research. The results have been published in the journal Nature Astronomy.
Jacob Isbell, a postdoctoral research associate at the U of A Steward Observatory and principal author of the Nature Astronomy study, stated, “The Large Binocular Telescope Interferometer can be viewed as the first extremely large telescope, making this a thrilling achievement.”
Every galaxy has a central supermassive black hole. Some of these are active, while others are dormant, based on the rate at which material is falling into them, according to Isbell. An accretion disk surrounds the black hole; it becomes more luminous as more material is gathered. If this disk is bright enough, the black hole is classified as active. The AGN located in galaxy NGC 1068, which is relatively close to our Milky Way, is among the brightest active examples.
The Large Binocular Telescope, perched on Mount Graham northeast of Tucson, operates with two 8.4-meter mirrors that function independently, effectively serving as two distinct telescopes side by side. The Large Binocular Telescope Interferometer merges the light from both mirrors, yielding much higher resolution observations than possible with either mirror alone. This advanced imaging technique has previously been employed to analyze volcanoes on Jupiter’s moon Io, prompting researchers to use the interferometer to investigate an AGN.
Isbell remarked, “The AGN in the galaxy NGC 1068 is incredibly bright, making it an ideal target to test this technology. These images represent the highest-resolution direct observations of an AGN to date.”
Steve Ertel, associate astronomer at Steward Observatory, leads the Large Binocular Interferometer Team. Utilizing the interferometer, the team was able to observe multiple cosmic phenomena occurring within the AGN simultaneously.
The luminous disk around the supermassive black hole emits significant light, which exerts radiation pressure, effectively pushing dust away like small sails. The images captured revealed a dusty, outwardly flowing wind caused by this radiation pressure. Additionally, there was an area further out emitting much more light than expected, given it was only illuminated by the bright accretion disk. By comparing the new images to older data, the scientists linked this phenomenon to a radio jet that is traversing the galaxy, interacting with and heating clouds of molecular gas and dust. Radio jet feedback refers to the effects of powerful jets of radiation and particles released from supermassive black holes on their surrounding environment.
The capability of extremely large telescopes like the Large Binocular Telescope Interferometer and the future 83.5-foot Giant Magellan Telescope in Chile enables researchers to differentiate between the feedback from the radio jet and the dusty wind concurrently. In the past, these different processes were merged due to lower resolutions; now, Isbell noted, the individual impacts can be clearly seen.
The findings of this study reveal that AGN environments are intricate, enhancing our understanding of how AGN interact with their host galaxies.
Isbell concluded, “This imaging technique can be applied to any astronomical body. We have already begun examining disks around stars or very large, evolved stars that have dusty envelopes surrounding them.”
