This Hubble Space Telescope image from the heart of the nearby active galaxy IC 5063 reveals a mixture of bright rays and dark shadows emanating from the burning core, home to a supermassive black hole. Astronomers suggest that a ring of dusty material around the black hole may cast its shadow into space. According to their scenario, this interaction between light and shadow can occur when light blown through the sample black hole hits the dust ring buried deep in the core. Light flows through gaps in the ring, creating the brilliant conical rays. However, denser spots on the disk block some of the light, casting long, dark shadows through the galaxy. This phenomenon is similar to sunlight penetrating our earthly clouds at sunset, creating a mixture of bright rays and dark shadows formed by rays of light scattered throughout the atmosphere. However, the bright rays and dark shadows that appear in IC 5063 happen on a much larger scale and shoot over at least 36,000 light-years. IC 5063 is 156 million light-years from Earth. The observations were taken on March 7 and November 25, 2019 by Hubble’s Wide Field Camera 3 and Advanced Camera for Surveys. Credit: NASA, ESA and WP Maksym (CfA)
Some of the most beautiful views of our sky occur at sunset, when sunlight passes through the clouds, creating a mixture of bright and dark rays formed by the shadows of the clouds and the rays of light scattered through the atmosphere.
Astronomers studying the nearby galaxy IC 5063 are teased by a similar effect in images taken NASAsay Hubble Space Telescope. In this case, a collection of narrow bright rays and dark shadows are seen radiating from the burning bright center of the active galaxy.
A team of astronomers, led by Peter Maksym of the Center for Astrophysics | Harvard & Smithsonian (CfA), in Cambridge, Massachusetts, traced the rays back to the galaxy’s core, the location of an active supermassive black hole. A black hole is a dense, compact space that swallows light and matter under the crushing force of gravity. The sample object feeds frantically on scrap material and produces a powerful light shimmer from overheated gas near it.
Although the researchers have developed several credible theories for the light show, the most interesting idea suggests that an inner tube-shaped ring, or torus, of dusty material around the black hole casts its shadow into space.
According to Maksym’s proposed scenario, the dust disk around the black hole does not block all the light. Through the gaps on the disk, light can radiate, creating radiant conical rays similar to the fingers of the light that can sometimes be seen at sunset. However, the rays in IC 5063 occur on a much larger scale and shoot over at least 36,000 light-years.
Some of the light hits dense spots in the ring and casts the ring’s shadow into space. These shadows appear as dark finger shapes interspersed with bright rays. These beams and shadows are visible because the black hole and the ring tilt sideways relative to the plane of the galaxy. With this alignment, the light rays can extend far beyond the galaxy.
This interaction between light and shadow provides a unique insight into the distribution of material surrounding the black hole. In some areas the material may look like scattered clouds. If this interpretation is correct, the observations can provide an indirect examination of the mottled structure of the disc.
“I’m most excited about the shadow of the torus idea, because it’s an amazing effect I’ve not seen in images before, even though it’s supposed to,” Maksym said. “Scientifically, it shows us something that is difficult – usually impossible – to see directly. We know that this phenomenon must happen, but in this case we can see the consequences in the entire galaxy. Learning more about the geometry of the torus will have consequences for anyone trying to understand the behavior of supermassive black holes and their environments. As a galaxy evolves, it is formed by its central black hole. ‘
The study of the torus is important because it hides material to the black hole. If the “shadow” interpretation is accurate, the dark rays provide indirect evidence that the disk in IC 5063 may be very thin, which explains why the light leaks around the structure.
Observations of similar black holes by NASA’s Chandra X-ray Observatory observed X-rays leaking from holes in the torus and making the structure look like Swiss cheese. The holes could be caused by the disk being closed by internal forces, causing it to warp, Maksym said. “It is possible that the warp creates gaps large enough to shine through the light, and when the torus rotates, rays of light can sweep through the galaxy like lighthouses through fog,” he adds.
Citizen Science Serendipity
Although astronomers have been studying the galaxy for decades, it is necessary for a non-scientist to make the surprising discovery. Judy Schmidt, an artist and amateur astronomer based in Modesto, California, exposed the dark shadows when she reworked Hubble’s exposure of the galaxy in December 2019. Schmidt regularly pulls out the Hubble archive for interesting observations that she can turn into beautiful images. She shares the images on her Twitter feed with her many followers, which include astronomers like Maksym.
Schmidt selected the Hubble observations from IC 5063 from the archive because she is interested in active galaxies. The cone-shaped shadows were not evident in the original exposure, and she was surprised to see them in her processed image. “I had no idea they were there, and even after I processed it, I kept blinking and wondering if I saw what I thought I was seeing,” she said.
She immediately posted her image on her Twitter account. ‘It was something I’ve never seen before, and although I strongly suspected it was shadow rays or’ crippled rays’, as Peter called it, it’s easy to let one’s imagination and wishful thinking run. , ‘she explained. . “I thought if I was wrong, someone would come and take me down.”
The image sparked a lively Twitter discussion among her astronomical followers, including Maksym, who discussed the origin of the rays. Maksym has already analyzed Hubble images of the rays produced by the black hole of the galaxy. Therefore, he took the lead in studying the rays and writing a science paper. His study is based on near-infrared observations made by Hubble’s Wide Field Camera 3 and Advanced Camera for Surveys in March and November 2019. Red and near-infrared light pierce the dusty galaxy to reveal the details that may have been shrouded in dust.
This discovery would not have been possible without Hubble’s sharp vision. The galaxy is also relatively close, only 156 million light-years from Earth. “Older images of telescopes on the ground may have shown hints of this kind of structure, but the galaxy itself is so cluttered that you’d never guess it would go on without Hubble,” Maksym explained. “Hubble has a sharp image, is sensitive to faint things and has a large field of vision to represent the entire galaxy.”
Maksym hopes to continue his study of the galaxy to determine if his scenario is correct. “We will want to keep researching, and it would be great if other scientists could also try to test our conclusions with new observations and modeling,” he said. “This is a project that only begs for new data because it raises more questions than it answers.”
The team’s results were published in 2008 The astrophysical journal letters.
Reference: “Crepuscular Rays from the Highly Inclined Active Galactic Nucleus in IC 5063” by W. Peter Maksym, Judy Schmidt, William C. Keel, Giuseppina Fabbiano, Travis C. Fischer, Joss Bland-Hawthorn, Aaron J. Barth, Martin Elvis , Tom Oosterloo, Luis C. Ho, Minjin Kim, Hyunmo Hwang and Evan Mayer, 8 October 2020, The astrophysical journal letters.
DOI: 10.3847 / 2041-8213 / abb9b6
The Hubble Space Telescope is a project of international collaboration between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, controls the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts scientific operations of Hubble. STScI is operated for NASA by the Association of Universities for Research in Astronomy in Washington, DC