The cosmic web is a large-scale cosmological structure made up of interconnecting filaments and gaps. It formed as a network-like structure as a result of the gravitational collapse of dark matter and subsequent accretion of ordinary matter. During the early phases of the universe’s evolution, the first strands of the cosmic web began to take shape shortly after the Big Bang.
Galaxies are not randomly distributed throughout the universe. They form not simply clusters, but massive interwoven filamentary formations with enormous barren spaces in between. This “cosmic web” began as a hazy thread and grew stronger over time as gravity brought stuff together.
Astronomers using NASA’s James Webb Space Telescope identified a thread-like pattern of ten galaxies 830 million years after the big bang. A brilliant quasar – a galaxy with an active, supermassive black hole at its heart — anchors the 3 million light-year-long structure. The researchers anticipate the filament will eventually form a large cluster of galaxies, similar to the well-known Coma Cluster in the nearby universe.
“I was surprised by how long and narrow this filament is,” said University of Arizona in Tucson team member Xiaohui Fan. “I expected to find something, but I didn’t anticipate such a long, distinctly thin structure.”
The last two decades of cosmology research have given us a robust understanding of how the cosmic web forms and evolves. ASPIRE aims to understand how to incorporate the emergence of the earliest massive black holes into our current story of the formation of cosmic structure.
Joseph Hennawi
“This is one of the earliest filamentary structures that people have ever found associated with a distant quasar,” said Feige Wang, the program’s chief investigator at the University of Arizona in Tucson.
The ASPIRE project (A SPectroscopic survey of biassed halos in the Reionization Era) made this discovery, which aims to explore the cosmic settings of the first black holes. The program will look at 25 quasars that existed in the first billion years following the big bang, a period known as the Epoch of Reionization.
“The last two decades of cosmology research have given us a robust understanding of how the cosmic web forms and evolves. ASPIRE aims to understand how to incorporate the emergence of the earliest massive black holes into our current story of the formation of cosmic structure,” explained team member Joseph Hennawi of the University of California, Santa Barbara.
Growing Monsters
Another part of the study investigates the properties of eight quasars in the young universe. The team confirmed that their central black holes, which existed less than a billion years after the big bang, range in mass from 600 million to 2 billion times the mass of our Sun. Astronomers continue seeking evidence to explain how these black holes could grow so large so fast.
“Two criteria must be met in order for these supermassive black holes to form in such a short period of time.” First, you must sprout from a massive ‘seed’ black hole. Second, even if this seed starts with the mass of a thousand Suns, it still needs to accrete a million times more matter at the fastest possible rate for the rest of its life,” Wang added.
“These unprecedented observations are providing important clues about how black holes are assembled. We have learned that these black holes are situated in massive young galaxies that provide the reservoir of fuel for their growth,” said Jinyi Yang of the University of Arizona, who is leading the study of black holes with ASPIRE.
Webb also offered the greatest evidence yet of how early supermassive black holes may influence star formation in their galaxies. While supermassive black holes absorb matter, they can also generate huge outflows of matter. On a galactic scale, these winds can stretch far beyond the black hole and have a profound impact on star formation.
“Strong winds from black holes can suppress star formation in the host galaxy.” Such winds have been recorded in the neighboring cosmos, but never directly observed in the Epoch of Reionization,” Yang explained. “The scale of the wind is related to the structure of the quasar.” The Webb observations show that such winds existed in the early universe.”
