Astronomers using NASA’s powerful James Webb Space Telescope may have solved one of the biggest mysteries of the early universe.
A strange object known as a “little red dot” appears to be a rapidly growing supermassive black hole hidden inside a thick cloud of gas.
Little red dots were first discovered by the James Webb Space Telescope in 2022.
These tiny, reddish objects appeared surprisingly often in the young universe, only a few hundred million years after the Big Bang.
Their discovery puzzled scientists because nobody knew exactly what they were.
Now, researchers studying one particular little red dot, called GLIMPSE-17775, have found the strongest evidence yet that these objects are actually what scientists call “black hole stars” or BH* objects.
The findings were published in The Astrophysical Journal.
GLIMPSE-17775 existed about 1.8 billion years after the Big Bang. It was observed behind a massive galaxy cluster, which acted like a natural magnifying glass through a phenomenon called gravitational lensing.
This magnification allowed Webb to collect an incredibly detailed spectrum—the most detailed ever obtained for a little red dot.
A spectrum is like a fingerprint of light. By breaking light into different wavelengths, astronomers can learn what an object is made of and what physical processes are happening inside it.
The researchers detected more than 40 different spectral lines from GLIMPSE-17775. These lines revealed several clues pointing to a black hole hidden within a dense cocoon of gas.
Many of the light signals from elements such as hydrogen, helium, and oxygen did not match what scientists would expect from a simple cloud of rotating gas.
Instead, they showed signs of electron scattering, a process that occurs when light passes through very dense material. This suggests that the object is surrounded by a thick layer of gas.
The team also found 16 iron-related spectral lines, which they nicknamed an “iron forest.” Producing such strong iron signals requires an extremely energetic source. A rapidly feeding supermassive black hole is one of the best explanations.
Additional evidence came from unusual helium features in the spectrum, which also indicate a powerful object hidden inside dense gas.
This model helps explain another mystery as well. Most little red dots appear surprisingly faint in X-rays. If a thick gas cocoon surrounds the black hole, it would absorb much of the X-ray radiation before it could escape.
The researchers combined Webb observations with data from NASA’s Hubble Space Telescope and discovered that GLIMPSE-17775 is also surrounded by a large host galaxy. This helps explain some of its unusual light patterns.
When little red dots were first discovered, some scientists wondered whether they challenged current theories of how the universe evolved. However, the new findings suggest that the universe may not be broken after all.
Instead, these mysterious objects may simply be growing black holes hiding behind thick curtains of gas. Scientists hope that future observations will finally reveal exactly what powers these fascinating cosmic objects.
