A new image of the first supermassive black hole to be pictured has revealed its swirling magnetic field. Since capturing the first photo in 2019, scientists have been trying to get deeper insights on the black hole in the centre of the M87 galaxy, which is 55 million light years from Earth. A global network of telescopes, called The Event Horizon Telescope (EHT), released the second photo on March 24. This time, researchers captured the massive object in polarised light – helping to reveal magnetic fields on the edge of the black hole. The observations could shed light on how the distant galaxy is able to launch energetic jets from its core. "We are now seeing the next crucial piece of evidence to understand how magnetic fields behave around black holes, and how activity in this very compact region of space can drive powerful jets that extend far beyond the galaxy," said Monika Moscibrodzka, a researcher for EHT. Showing the black hole in polarised light helped scientists to see intimate details around the object. Similar to polarised sunglasses, the effect reduces glare and sharpens the image. The high resolution of the black hole image is equivalent to measuring the length of a credit card on the lunar surface. Eight telescopes around the world were linked to capture the object. "This work is a major milestone. The polarisation of light carries information that allows us to better understand the physics behind the image we saw in April 2019, which was not possible before," said Ivan Marti-Vidal, another researcher. “Unveiling this new polarised-light image required years of work due to the complex techniques involved in obtaining and analysing the data.” Newer insights on the magnetic fields will help researchers to understand the mysterious energetic features of the black hole’s galaxy. The image mapped magnetic fields in extreme gravity, which could show how it is connected to the powerful jets of energy and matter that are emitted from M87's core. Energy from the jets extends 5,000 light years from its centre, but most of the matter close to the edge falls in. Some of the surrounding particles escape moments before being captured and are blown far out into space in the form of jets. “The polarimetric images suggest that the magnetic fields near the black hole could be strong enough to prevent matter from falling under the event horizon. The gas surrounding the black hole can be easily turned into a jetted outflow,” Ms Moscibrodzka said.