Posted by New Delhi: Astronomers have captured in polarised light the strong magnetic fields spiraling out from the edge of Sagittarius A* (Sgr A*), the supermassive black hole lurking in the core of the Milky Way. Sgr A* is at a distance of 27,000 lightyears from the Earth, and its shadow, or the event horizon, the region from which even light cannot escape, was captured for the first time in 2022, by the Event Horizon Telescope collaboration. The collaboration has subsequently tracked light escaping from the edge of Sgr A* and reconstructed a photon ring surrounding the object, confirming theoretical predictions.
The new image reveals the magnetic fields in polarised light for the first time, with the structure being remarkably similar to the black hole at the centre of the M87 galaxy, indicating that structures may be present on all supermassive black holes. Studies have previously indicated that the magnetic fields around the black hole launch energetic jets of light. The researchers suspect that such jets may be being produced by Sgr A* as well, but these are hidden from view.
Co-lead of the project, Sara Issaoun says, “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. Along with Sgr A* having a strikingly similar polarization structure to that seen in the much larger and more powerful M87* black hole, we’ve learned that strong and ordered magnetic fields are critical to how black holes interact with the gas and matter around them.”
What is the EHT Collaboration
The EHT collaboration consists of more than 400 scientists from countries around the world. The researchers are using an Earth-sized virtual telescope to assemble the most detailed images of supermassive black holes ever captured. The images produced by the collaboration are averages of many, many individual exposures. The individual telescopes participating in the collaboration changes all the time.