Iván Martí-Vidal, EHT Polarimetry Working Group coordinator and researcher at the University of Valencia in Spain, said: “This work is a major milestone: The polarization 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.
“Unveiling this new polarized light image required years of work due to the complex techniques involved in obtaining and analyzing the data.”
Light becomes polarized in one of two ways: When it passes through a filter – like lenses on polarised sunglasses – or when it is emitted from a scorching-hot region of space where magnetic fields are present.
And just like a pair of polarised sunglasses makes it easier to see on a sunny day, astronomers can use this phenomenon to get a better view of the black hole in question.
More specifically, the polarised light allows scientists to chart the magnetic fields that flow near the black hole’s edge.