Massive Filaments Connect Galaxies and Fuel the Supermassive Black Holes

How do galaxies form? What do black holes lead to? Where did matter come from, anyway? What caused the Big Bang? What is Dark Energy, actually? How did the laws of physics occur, and why are they inviolably? Will the Universe’s existence ever end? Will time itself end some day? Why do we exist at all? Most people, even astrophysicists, acknowledge that most likely, we’ll never have irrefutable answers to all of these crucial questions. But at least science is looking for answers by using the best tools at the moment.

The Multi Unit Spectroscopic Explorer (MUSE) at the ESO Very Large Telescope (VLT) in Chile and the Suprime-Cam at the Subaru telescope had been the main source of inspiration for An international group of scientists led by the RIKEN Cluster for Pioneering Research. They found out something shocking.

Filaments of gas connecting galaxies are extensive and the main fuel provider

By making detailed observations of the filaments of gas connecting galaxies in a large, distant proto-cluster named SSA22, scientists concluded that the filaments are extensive, extending over more than 1 million parsecs and are providing the fuel for intense formation of stars and for the growth of supermassive black holes within the proto-cluster.

Although scientists initially thought that galaxies form and later organized into clusters by the effects of gravity, now the scientists led by the RIKEN Cluster for Pioneering Research are offering a new view: the intersection between the enormous filaments they identified is home to active galactic nuclei—supermassive black holes—and galaxies that have very active star formation. This claim is based on the generally accepted idea among astrophysicists that filaments in the universe fueled the formation of clusters of galaxies and galaxies at places where the filaments crossed, creating dense regions of matter.

According to Hideki Umehata of the RIKEN Cluster for Pioneering Research and the University of Tokyo, the first author of the paper, “This suggests very strongly that gas falling along the filaments under the force of gravity triggers the formation of starbursting galaxies and supermassive black holes, giving the universe the structure that we see today.”

He also added: “Previous observations had shown that there were emissions from blobs of gas extending beyond the galaxies, but now we have been able to clearly show that these filaments are extremely long, going even beyond the edge of the field that we viewed. This adds credence to the idea that these filaments are actually powering the intense activity that we see within the galaxies inside the filaments.”

The work of the scientists is based on the detection of Lyman alpha radiation, using the MUSE instrument. Lyman alpha radiation means ultraviolet light that is produced when neutral hydrogen gas is ionized and then returns to its ground state. The radiation was found to be too intense to come from the ultraviolet background radiation of the Universe, thus they calculated that the high radiation was triggered by star forming galaxies and forming black holes.

The new findings by the scientists led by the RIKEN Cluster for Pioneering Research were published in Science magazine.