New observations hint at causes of powerful jets

Photo first: a black hole expelling a powerful jet has never been directly imaged before

For the first time, astronomers have captured both the shadow of a black hole and its powerful jet in the same image. The picture of the heart of galaxy M87 was taken in 2018 using radio observatories around the world working as one to create a single, Earth-sized telescope, but it has taken several years to process the data.

“We know that jets are ejected from the region surrounding black holes,” says Ru-Sen Lu from the Shanghai Astronomical Observatory, China, “but we still don’t fully understand how this happens. To study this directly we need to observe the origin of the jet as close as possible to the black hole.”

M87’s black hole made history as the first to be imaged by the Event Horizon Telescope in 2019, but the new studies were at 3.5mm rather than 1.3mm. At these longer wavelengths, the team saw the region where the jet connects with the ring of emission around the central supermassive black hole, which will give key insights into how these jets form. www.eso.org