Small, compact, red-tinted galaxies discovered in 2024 are thought to have existed in the early universe, between 0.6 and 1.6 billion years after the Big Bang. Now, similar objects have been discovered very close to our planet. This could completely change our understanding of how such bodies are born.
Since its launch, NASA’s space telescope (JAMES WEBB)has provided astronomers with a huge data set about the early universe. The spacecraft’s unprecedented sensitivity to infrared light has allowed scientists to peer further and deeper into the past than ever before.
What Are ‘Little Red Dots’ Galaxies?
Among the most intriguing discoveries of the American observatory are compact red objects, which were named “ little red dots” (Little Red Dots) They have only been seen in the farthest reaches of the universe. Most arose during the first billion years after the Big Bang, and scientists assumed they were somehow related to processes unique to that era.
Astronomers belived, that these objects may be nascent supermassive black holes, just beginning to absorb matter or form inside the very first galaxies. It was thought that such bodies simply could not exist in the more mature and quiet modern Universe: there are not enough conditions and fuel for such compact objects to be forming or “burning” so actively. Because of the remoteness of the “little red dots,” studying them was incredibly difficult even with the most modern telescopes.
Why the New Discovery Is So Surprising
Now, an international team of astronomers led by Xiaojing Lin has found something unexpected. Scientists have discovered “little red dots” in a much more recent universe. The light from these objects took 2.5 billion years to reach Earth. That’s almost six times closer than earlier analogs.
How the Galaxies Were Found Using Sloan Digital Sky Survey
To search, the team used data from the Sloan Digital Sky Survey, a large-scale study of multispectral images and redshift spectra of stars and galaxies using the 2.5-meter wide-angle telescope at Apache Point Observatory in New Mexico (USA). It is the largest database of space images.
Meet the New ‘Little Red Dots’ — Including “The Egg”
In these images, Lin and his colleagues found three galaxies that, by all indications, fully match the parameters of the “little red dots.” One of them even received the nickname “Egg” for its elongated shape.
Each of them has a mass approximately one million times greater than the Sun, while their size is comparable to the Solar System – extremely compact by the standards of galaxies.
Moreover, scientists have found several more possible candidates for this class of objects. However, additional observations are needed to confirm their belonging.
What This Means for Our Understanding of Galaxy Evolution
Why is this discovery so important? Until now, scientists thought that such galaxies could only exist in the early Universe. But the new discovery suggests otherwise. The conditions under which such objects arise can be repeated even 12 billion years after the Big Bang. That is, the very nature of these galaxies is not limited by era.
The objects are close enough for space telescopes to study them in detail: their light is brighter and clearer. Scientists will be able to study the structure of the “little red dots,” their composition, and perhaps learn how they form and evolve.
Theories Behind the ‘Little Red Dots’
It is quite possible that such galaxies represent the initial stages of growth of supermassive black holes. This is the moment when the black hole is just starting the process of actively absorbing matter. There is another scenario: these objects could have simply been inactive for most of history and are only now beginning the active phase. Or they have recently formed and are starting to “feed”.
What Comes Next in the Research?
Lin’s team has already applied for observation time with the Hubble Space Telescope. Once approved, the scientists will get more detailed images of the objects and be able to unravel their nature.
Astronomers’ conclusions published on the website of the Cornell University Electronic Archive of Scientific Articles.
