Emily Chan
It was a challenge to find black holes that existed in the first billion years of the universe. Their brightness varies over time, so they are easy to miss.
The research team tracked some of the earliest galaxies for changes in brightness over the course of 15 years. Then, they used the data to determine how many black holes were out there.
It turned out that there were many more black holes in early galaxies than previously thought. Overall, more black holes are present than can be explained by direct collapse.
A third hypothesis could explain the phenomenon. If large numbers of dark matter particles are captured when stars form during the gravitational contraction of gas clouds, then the stars’ internal structures can be completely altered.
Therefore, the growth of black holes can continue for far longer than the average lifetime of a regular star, allowing them to reach humongous sizes.
It is likely that a similar process took place to result in the many supermassive black holes observed in the early universe.
The study of early black hole formation is only just beginning. Next, astronomers must keep an eye out for the observations that the James Webb Space Telescope is making.
The details of the findings were published in Astrophysical Journal Letters.
