An optical image of the spiral galaxy NGC 1086 (Messier 77) overlaid with an inset with the image obtained by the Large Binocular Telescope Interferometer (LBTI) at thermal infrared wavelengths (8.7 micrometers). – ESO / J. ISBELL (UOFA, MPIA) / MPIA
Jan. 17 () –
Observations with the Large Binocular Telescope (LBT) have produced the best infrared images of a active galactic nucleus (AGN): a supermassive black hole in action.
The findings are published in the journal Nature Astronomy.
Every galaxy has a supermassive black hole at its center. Some of them are considered active while others are inactive, depending on the speed with which the material falls on them. Around the black hole there is a disk that shines brighter the more material there is. If this accretion disk shines bright enough, it is called an active supermassive black hole. The AGN that exists in the galaxy NGC 1068, neighboring the Milky Way, is one of the closest ones that is considered active.
The LBT is located on Mount Graham, Arizona. It operates its two 8.4-meter mirrors independently, essentially functioning as two separate telescopes mounted side by side.
The Large Binocular Telescope Interferometer combines light from both mirrors, allowing observations to be made with much higher resolution than would be possible with each mirror alone. This imaging technique has been used successfully in the past to study volcanoes on the surface of Jupiter’s moon Io. The Jupiter results encouraged researchers to use the interferometer to observe an AGN.
“The AGN within the galaxy NGC 1068 is especially bright, so it was the perfect opportunity to test this method,” said Jacob Isbell, a postdoctoral research associate at the University of Arizona’s Steward Observatory and lead author of the paper. ““These are the highest resolution direct images of an AGN taken so far.”
The bright disk around the supermassive black hole releases a lot of light, which pushes the dust outward like tiny candles, a phenomenon known as radiation pressure. reports the Max Planck Institute for Astronomywho participated in the study.
The images revealed an expanding dusty wind caused by radiation pressure. At the same time, further away, there was a lot of material that was much brighter than it should have been, considering that it was illuminated only by the bright accretion disk.
By comparing the new images with previous observations, the researchers were able to link this finding to a radio jet passing through the galaxy, hitting and heating clouds of molecular gas and dust. Radio jet feedback is the interaction between powerful jets of radiation and particles emitted by supermassive black holes and their surrounding environment.
The study shows that the environments of AGNs can be complex, and the new findings help to better understand the interaction of AGNs with their host galaxies.
“This type of images can be used on any astronomical object“Isbell said. “We have already begun to observe disks around stars or very large, evolved stars, which have dust envelopes around them.”
Add Comment