The mysterious Little Red Dots in the Universe are gigantic stars after all

The Little Red Dots have been a point of contention since their discovery. Now, a new study suggests that the star lurks at the center of these massive objects, and is a single gigantic star in a fragile envelope.

Using data from NASA’s James Webb Space Telescope, astronomers at the Center for Astrophysics | Harvard & Smithsonian have revealed that the most mysterious distant objects in the Universe, known as Small Red Dots (or LRDs, an acronym for “Little Red Dots”), may actually be gigantic, short-lived stars.

The findings offer a direct glimpse into how the Universe’s first supermassive black holes may have been formed, marking a breakthrough in scientists’ understanding of the universe. primitive cosmos.

The , pre-published on arXiv, was presented last week at a press conference during the 247th meeting of the American Astronomical Society in Phoenix, in the US state of Arizona.

As the Universe expands, the light from very distant objects acquires redder colors. The first space telescopes, like Hubble, were built to detect shorter wavelengths of light, and although they saw interesting targets that later turned out to be LRDs, scientists couldn’t tell exactly what they were.

In 2022, the first deep images of Webba telescope designed to view longer wavelengths, revealed tiny red dots on the Distant universe.

In August last year, a theory suggested that these spots could be , which would have gone completely unnoticed before the James Webb Space Telescope.

The new results gave scientists more contexto about what these mysterious, compact and very ancient objects could be.

Previous theories to explain Little Red Dots required complicated explanations involving black holesaccretion disks and dust clouds.

But the new model shows that a single massive star tIt can also naturally produce all of the key signatures of LRDs: extreme brightness, a distinct V-shaped spectrum, and the rare combination of brilliant hydrogen emission.

Now, for the first time, astronomers created a detailed physical model of a rare, metal-free, fast-growing supermassive star about a million times the mass of the Sun, and showed that its unique features are a perfect match for the Little Red Dots.

“The Little Red Dots have been a point of contention since its discovery”, Devesh Nandalastronomer at the Astrophysics Center | Harvard & Smithsonian and lead author of the new study.

“But now, with the new modeling, we know what is hidden in the center of these massive objects, and It is a single gigantic star in a fragile envelope. And, most importantly, these discoveries explain everything Webb has been seeing.”

While stars of a wide range of masses align with both spectral measurements for the LRDs, only the most massive have the correct brightness.

Nandal and his colleagues think that if they can find more Little Red Dots that are less luminous and massive than those in the study, will be able to discover the truth about why and how this happens.

The new results are helping scientists take a step forward in understanding Little Red Dots by providing direct evidence of the final and shining moments that occur immediately before a giant star collapses into a black hole.

“If our interpretation is correct, nWe’re not just guessing that there must have been massive ‘seeds’ of black holes. Instead, we are see some of them born in real timeNandal said.

“This gives us much stronger knowledge about how supermassive black holes and galaxies in the Universe grew,” he concludes.