A groundbreaking image of the black hole at the center of our galaxy, released in 2022, might not be as accurate as initially thought, say researchers from Japan’s National Astronomical Observatory (NAOJ). After years of work, the Event Horizon Telescope (EHT) team managed to capture the first-ever image of the black hole known as Sagittarius A*, or Sgr A*, located roughly 26,000 light-years from Earth. However, a new analysis suggests that the famous “doughnut” shape could be misleading.
Sagittarius A*, or Sgr A*, has long been an extremely challenging object to capture in an image. It’s surrounded by material moving nearly at the speed of light, which makes capturing a clear image very difficult, according to reports from Space.com. The 2022 EHT project succeeded in producing an image of Sgr A*, showing it as a bright ring-like structure with a dark center. Yet, according to NAOJ, the black hole’s true appearance might differ, with its actual shape potentially more elongated than the ring in the EHT image.
NAOJ scientists applied new analysis methods to the original data collected by the EHT, leading them to question some elements of the initial image. Their analysis indicated that the bright ring may not be perfectly round, but instead could be stretched out, particularly in the east-west direction. This suggests that what appeared to be a ring might actually have been influenced by image processing methods.
The process of capturing an image of something as distant and unique as a black hole is complex and relies on data from telescopes across the globe. Miyoshi Makoto from NAOJ notes that telescopes have limitations, and no single instrument can provide a flawless astronomical image.
“We think this appearance means the accretion disk surrounding the black hole is rotating at about 60% of the speed of light,” says Miyoshi.
He adds that part of the ring structure might be the result of imaging errors, rather than the actual structure of Sgr A*.
Miyoshi went on to explain that the brightness on the eastern side of the black hole’s disk compared to the western side could be due to these data assembly techniques. The possibility that imaging artifacts influenced the final photo adds complexity to interpreting the visual appearance of black holes, which are already hard to observe directly.
As of now, the EHT team has not made any public statements in response to the new analysis. However, this study from NAOJ highlights the challenges astronomers face when imaging such distant and complex objects. It underscores the importance of ongoing research and new analysis techniques in refining our understanding of cosmic phenomena like black holes.
The question of what Sgr A* truly looks like may take years to fully resolve, but one thing is certain—the journey to understand these mysterious objects is far from over.
