Peering into the heart of our galaxy with unprecedented clarity, astronomers have recently released a new image that offers a glimpse of the magnetic maelstrom surrounding Sagittarius A* (Sgr A*), the supermassive black hole at the Milky Way’s center. Captured in polarized light, this image isn’t just a beautiful cosmic snapshot; it’s a vital clue in understanding the enigmatic phenomena of black holes.
“What we’re seeing now is that there are strong, twisted, and organized magnetic fields near the black hole at the center of the Milky Way galaxy,” stated Sara Issaoun, a project co-leader and NASA Hubble Fellowship Program Einstein Fellow at the Center for Astrophysics at Harvard & Smithsonian. The revelation comes from the Event Horizon Telescope (EHT) collaboration, which links eight telescopes around the world to function as a single planet-sized instrument.
The new polarized light image of Sgr A* offers a startling spiral structure of magnetic fields. Such detailed imagery of a black hole’s magnetic field is a significant leap from the first image of Sgr A* released two years ago, which showed glowing gas around a dark center. The new visualization provides insights into the “swirl of gas and material that orbits a dark central region,” a critical component in understanding black hole dynamics.
Echoing a universal trait among its kind, the magnetic field of Sgr A* bears a striking resemblance to the field observed around the supermassive black hole in the M87 galaxy, despite their size differences. M87’s black hole, known as M87*, is vastly larger and more massive than our local cosmic beast, yet they share a similar polarization structure.
These observations bring us closer to decoding the mysteries of how black holes interact with their environment. “We’ve learned that strong and ordered magnetic fields are critical to how black holes interact with the gas and matter around them,” Issaoun added. The comparison between M87* and Sgr A* in polarized light has intrigued researchers, hinting at possible common behaviors across black holes of different scales.
Polarized light imaging is akin to the effects of polarized sunglasses, enhancing clarity by filtering light oscillations to a single plane.“By imaging polarized light from hot glowing gas near black holes, we are directly inferring the structure and strength of the magnetic fields that thread the flow of gas and matter that the black hole feeds on and ejects,” explained Angelo Ricarte, a Harvard Black Hole Initiative fellow and project co-lead.
However, capturing these images is no simple task. Sgr A* is notoriously evasive for such photography, changing rapidly and defying static representation. “Sgr A* is changing so fast that it doesn’t sit still for pictures,” the researchers highlighted. Hence, the polarization image of Sgr A* is indeed an achievement in astronomical imaging.
The insights gained from these polarized light images are not only significant for understanding individual black holes but also hint at broader astrophysical principles. Mariafelicia De Laurentis, EHT Deputy Project Scientist, suggested, “The fact that the magnetic field structure of M87* is so similar to that of Sgr A* is significant because it suggests that the physical processes that govern how a black hole feeds and launches a jet might be universal among supermassive black holes.”
BY ETHAN BROWN