With the assistance of NASA’s Hubble Space Telescope, a global team of scientists has discovered a greater number of black holes in the early universe than previously identified. This significant finding may help researchers comprehend the formation of supermassive black holes.
Utilizing NASA’s Hubble Space Telescope, an international team led by researchers from the Department of Astronomy at Stockholm University has uncovered more black holes in the early universe than were known before. This new discovery could provide insight into the origins of supermassive black holes.
At present, scientists lack a full understanding of how the first black holes emerged shortly after the big bang. Evidence suggests that supermassive black holes, which can exceed the mass of a billion suns, were already present at the centers of some galaxies within less than a billion years post big bang.
“A lot of these objects appear to be more massive than we initially believed possible at such early times — either they formed with significant mass or experienced rapid growth,” explained Alice Young, a PhD student from Stockholm University and a co-author of the study published in The Astrophysical Journal Letters.
Black holes are crucial in the life cycle of galaxies; however, there are still significant gaps in our knowledge of galaxy evolution. To build a clearer understanding of the relationship between the evolution of galaxies and black holes, the researchers utilized Hubble to analyze the number of black holes found among a set of dim galaxies during a period when the universe was just a few percent of its current age.
The initial observations of the survey area were revisited by Hubble years later. This enabled the team to track changes in the brightness of galaxies, a key indicator of black hole presence. They were able to identify a higher number of black holes compared to previous techniques.
These new findings imply that some black holes likely originated from the collapse of large, primitive stars within the initial billion years of cosmic history. Such stars can only exist in the universe’s early stages because stars from later generations are affected by the remnants of pre-existing stars. Other possibilities for black hole formation include the collapse of gas clouds, the merging of stars in massive clusters, and “primordial” black holes that may have formed through speculative mechanisms in the seconds following the big bang. This fresh evidence about black hole formation can lead to more precise models for how galaxies are formed.
“Understanding how early black holes formed is a crucial piece of the larger puzzle of galaxy evolution,” noted Matthew Hayes from the Department of Astronomy at Stockholm University and the study’s principal author. “Alongside our models for black hole growth, galaxy evolution simulations can now be more accurately based on physical principles, offering a reliable framework for understanding how these black holes originated from collapsing massive stars.”
Astronomers are also conducting observations with NASA’s James Webb Space Telescope to investigate galactic black holes that formed shortly after the big bang, aiming to determine their size and locations.
