A groundbreaking image captures a jet of material emerging from a black hole for the first time.The black hole in question is a supermassive one located at the core of Messier 87 (M87) galaxy. The image was obtained in 2018 through the collaborative efforts of several telescopes.
The image is a breakthrough in astronomy that can potentially provide valuable insights into the behavior of black holes and the mechanism behind their ability to launch energetic material jets across the universe. To obtain the image, the Atacama Large Millimeter/submillimeter Array in Chile, the Greenland Telescope, and the Global Millimeter VLBI Array of telescopes from Europe and North America collaborated to create a virtual telescope with the size of the Earth. Using this powerful tool, they peered into the core of M87, a galaxy located 55 million light-years away from Earth.
The black hole situated at the center of M87 has a mass 6.5 billion times greater than that of the sun. Typically, a supermassive black hole resides in the center of a large galaxy, where it consumes gas, dust, and stars that pass too closely. However, some black holes can also emit high-energy jets of material that shoot across space, extending beyond their host galaxies.
The research paper and the groundbreaking image were both released on Wednesday in the journal Nature. Lead study author Ru-Sen Lu, an astronomer at the Shanghai Astronomical Observatory in China, explained in a statement that while scientists are aware of the ejection of jets from the region surrounding black holes, the exact process behind it remains unclear. To investigate the matter directly, it is necessary to observe the jet's origin as closely as possible to the black hole.
The new image presents a connection between the swirling matter surrounding the supermassive black hole and the base of the jet, which was not visible in previous observations. This includes the first direct image of a black hole that was published in 2019, where the jet and black hole were observed separately. As explained by study coauthor Jae-Young Kim, an assistant professor at Kyungpook National University in South Korea, the new image fills in the gaps by displaying the region around the black hole and the jet simultaneously.
When matter revolves around the black hole, it generates heat and releases radiation in various wavelengths of light. This light forms the glowing ring structure observed surrounding the black hole's shadow or the central darkness. The new image captured radio light at longer wavelengths than the 2019 image. According to Thomas Krichbaum, a research fellow at the Max Planck Institute for Radio Astronomy and a coauthor of the study, this longer wavelength allowed them to observe how the jet emerges from the ring of emission around the supermassive black hole's center.
An illustration showing how the black hole's massive jet rises up from the center
The ring's size depicted in the new image is around 50% larger than the 2019 image captured by the Event Horizon Telescope Collaboration, which is another global network of telescopes that photographed the M87 black hole. Astronomers believe that the reason for the ring's enlargement in the new image is the increased amount of material falling toward the black hole. To produce the image, the researchers utilized interferometry, which is a technique that synchronizes the signals gathered by each telescope.
Astronomers have recently employed machine learning to produce an enhanced and sharper version of the original M87 black hole image captured in 2019. The image shows a larger, darker central region surrounded by a bright ring, which results from hot gas falling into the black hole.
Black holes are incredibly massive objects formed by compressing huge amounts of matter into a relatively small area. As described by NASA, this generates an immensely powerful gravitational field that attracts everything in its vicinity, including light. These celestial objects also possess the capability to superheat the matter around them and cause a curvature in the fabric of space-time.
Material is drawn towards black holes, gets heated to billions of degrees, and accelerates to almost the speed of light. The gravity of the black hole bends light, forming the photon ring observed in the image. The dark central region in the image depicts the shadow of the black hole.
Albert Einstein's theory of general relativity is confirmed by the visual evidence of black holes. Einstein predicted that extremely dense regions of space would have such strong gravity that nothing could escape them. The visibility of the event horizon through the emission of light from heated plasma surrounding the black hole confirms this theory.
Observations of black holes by global telescope networks have the potential to reveal more secrets about these mysterious objects.
According to coauthor Eduardo Ros, scientific coordinator of the department for very long baseline interferometry at the Max Planck Institute for Radio Astronomy:
We plan to observe the region around the black hole at the centre of M87 at different radio wavelengths to further study the emission of the jet. The coming years will be exciting, as we will be able to learn more about what happens near one of the most mysterious regions in the Universe.- Eduardo Ros, scientific coordinator of the department for very long baseline interferometry at the Max Planck Institute for Radio Astronomy