Group picture of the workshop which triggered the imaging of the magnetic fields at the Max-Planck-Institut für Radioastronomie in Bonn, Germany, on July 15-19, 2019 [IMAGE: E. TRAIANOU/MPIFR]

The Event Horizon Telescope (EHT) collaboration, which produced the first ever image of a black hole, revealed a new view of the massive object at the centre of the M87 galaxy on March 24, 2021: how it looks in polarized light. This is the first time astronomers have been able to measure polarization, a signature of magnetic fields, this close to the edge of a black hole. The observations are key to explaining how the M87 galaxy, located 55 million light-years away, is able to launch energetic jets from its core.

A view of the M87 supermassive black hole in polarized light: This image shows the polarized view of the black hole in M87. The lines mark the orientation of polarization, which is related to the magnetic field around the shadow of the black hole. [IMAGE: EHT COLLABORATION]

With the new EHT image of the black hole and its shadow in polarized light, astronomers managed for the first time to look into the region just outside the black hole where this interplay between matter flowing in and being ejected out is happening.

The observations provide new information about the structure of the magnetic fields just outside the black hole. The team found that only theoretical models featuring strongly magnetized gas can explain what they are seeing at the event horizon.

More than 300 scientists from various organizations and universities around the globe, including researchers from the Shanghai Astronomical Observatory (SHAO) of the Chinese Academy of Sciences, are participating in this research.

Source: EHT Collaboration