A Fresh View of an Increasingly Familiar Black Hole

A patch of pure nothing in a faraway galaxy has lately become the gravitational center of attention for radio astronomers. That would be a giant black hole, with the gravity of 6.5 billion suns, that spits high-energy particles from the center of the galaxy Messier 87, which lies some 50 million light-years from Earth.

In 2019, astronomers operating a network of radio telescopes known as the Event Horizon Telescope dazzled the world by producing a radio map of the entity — the first-ever image of a black hole. It showed a fuzzy doughnut of energy, the glowing radiation produced by doomed matter circling the dark door to eternity.

Last month a subset of the same team, using artificial intelligence to analyze the original data, generated a sharper image that showed a thinner doughnut of doom surrounding an even blacker center.

Now a third group of astronomers has harnessed a different global web of observatories — including the Global Millimeter VLBI Array, the Atacama Large Millimeter/submillimeter Array in Chile and the Greenland Telescope — to capture a zoomed-out view of the black hole. Their image shows, for the first time, the base of the well-studied jet of energy and particles that arises from the center of the M87 galaxy and shoots across interstellar space. The image, generated by a vast international team led by Ru-Sen Lu from the Shanghai Astronomical Observatory in China, was published on Wednesday in the journal Nature.

By observing its subject at slightly longer radio wavelengths, the team was able to bring into visibility the cooler outer regions of the black hole’s fiery accretion disk, from which the jet seems to emanate.

We know that jets are ejected from the region surrounding black holes,” Dr. Lu said in a statement issued by the European Southern Observatory. But we still do not fully understand how this actually happens. To study this directly we need to observe the origin of the jet as close as possible to the black hole.”

In the meantime, the Event Horizon Telescope team is gathering resources for more observations, with the goal of making a black-hole movie.

Kazunori Akiyama, an astrophysicist at the Haystack Observatory at the Massachusetts Institute of Technology and a member of the Event Horizon project and an author of the new image, said, “I’m really excited to see this result, because now we have a new tool to capture what is surrounding the famous E.H.T.’s black hole. We will be able to film how the matter falls into a black hole and eventually manages to escape.”

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