Astronomers have discovered the most distant black hole yet seen in X-rays using two NASA telescopes, the Chandra X-ray Observatory and James Webb Space Telescope. The black hole is at an early stage of growth that had never been witnessed before, where its mass is similar to that of its host galaxy.
This result may explain how some of the first supermassive black holes in the universe formed.
By combining data from Chandra and Webb, a team of researchers was able to find the telltale signature of a growing black hole just 470 million years after the Big Bang. The extremely distant black hole is located in the galaxy UHZ1 in the direction of the galaxy cluster Abell 2744. The galaxy cluster is about 3.5 billion light-years from Earth. However, the Webb data reveal that UHZ1 is actually much farther away than Abell 2744. At some 13.2 billion light-years away, astronomers are seeing UHZ1 when the universe was only 3% of its current age.
By using over two weeks of observations from Chandra, the researchers were able to detect X-ray emission from UHZ1. This is a telltale signature of a growing supermassive black hole in the center of the galaxy. The X-ray signal is extremely faint and Chandra was only able to detect it — even with this long observation — because of the phenomenon known as gravitational lensing that enhanced the signal by some 400%.
This discovery is important for understanding how some supermassive black holes can reach colossal masses soon after the big bang. Do they form directly from the collapse of massive clouds of gas, creating black holes weighing between about ten thousand and a hundred thousand suns? Or do they come from explosions of the first stars that create black holes weighing only between about ten and a hundred suns?
The researchers suggest this is the best evidence yet obtained that some black holes form from massive clouds of gas. They plan to use this and other results pouring in from Webb and those combining data from other telescopes including Chandra to help fill out a larger picture of black holes in the early universe.
Revised: December 01, 2023