Astronomers were baffled by JWST data a little more than two years ago. We observed certain galaxies that appeared to defy our preconceived notions. They were just too large to have developed in the few hundred million years that separated them from the beginning of the universe, if the light we were receiving from them was emanating from their stars. Researchers had long thought that the anomaly was caused by black holes, and now they have some crucial confirmation.
Supermassive black holes at galaxies’ centers and the galaxies that hold them grow together in the modern universe. For the oldest galaxies, however, this may not be the case. It is thought that the so-called Little Red Dots (LRDs) belong to a brand-new class of galaxies that were exclusive to the early universe.
After the Big Bang, all of these galaxies formed about 600 million years ago and continued to exist for the first 1.5 billion years. That time frame is referred to as high redshift in astronomy. The scientists estimated that 70 percent of LRDs have gas revolving at 1,000 kilometers per second (2 million miles per hour), indicating the presence of a supermassive black hole, based on observations of these objects from numerous publicly available surveys from JWST.
In a statement, lead author Dale Kocevski of Colby College said, “A lot of work is being done to try and determine the nature of these little red dots and whether their light is dominated by accreting black holes.”
Scientists have not discovered any proof that these objects conceal a supermassive black hole at various wavelengths; in particular, X-rays show nothing. This is not wholly unexpected, as studies have revealed that black holes at galaxies’ centers are frequently covered in dense gas clouds, a phenomenon that still exists today.
There isn’t an equivalent nowadays, though. If the model is right, these sources’ black holes—rather than their stars—dominate them. Even if these sources are no longer in existence, they become smaller and lighter when a growing black hole is taken into consideration, despite the first research indicating that they were too huge to exist.
“The redshift distributions are what I find most intriguing. According to Steven Finkelstein, a co-author of the work from the University of Texas at Austin, “these really red, high-redshift sources basically stop existing at a certain point after the Big Bang.” “This suggests an era of hidden black hole growth in the early universe if they are growing black holes, which we believe at least 70% of them are.”
The group is using theory and fresh data to look into a number of unanswered topics. For example: do these black holes actually have a deep shroud? Why are these things no longer around? While having them as a new class addresses one issue, it also poses additional ones.
Kocevski asserted that there are always two or more possible explanations for the perplexing characteristics of small red dots. “Models and observations are constantly being exchanged, and a balance must be struck between what works well and what doesn’t.”
