Astronomers had goosebumps: The most distant galaxy ever discovered from distant ages 13.5 billion years ago was described in a study on Friday whose results have not yet been confirmed by further observations.
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Using four telescopes to observe the sky for more than 1,200 hours and discovering the luminous object “HD1”, its discoverer Yuchi Hurricane explains that “the color red is surprisingly similar to the properties of a galaxy located 13.5 billion years old”. A press release issued on the sidelines of a study by The Royal Astronomical Society.
An intuition confirmed by additional data collected by the Alma Laboratory in Chile: HD1 is 100 million years farther away than GN-z11, setting a record for the farthest galaxies ever.
The galaxy HD1 was born about 300 million years after a periodic eruption of the primitive universe. And the light emitted from it would have traveled 13.5 billion years to reach Earth.
To determine its age, scientists measured the red change of its original light. As the universe expands, the space between objects expands. And the farther we go back to the past, the farther away these objects are, the more their light lengthens and increasingly moves towards the red wavelengths.
“When I discovered this red color, I had duck bumps,” says an astronomer from the University of Tokyo, one of the authors of the study, which was published in the Journal of Astrophysics.
But there is a catch: scientists have measured the exceptionally strong intensity of ultraviolet radiation there, which is a sign of a process that does not consider theoretical models of galaxy formation.
The authors of the study then put forward two hypotheses: it would have been a particularly fertile ground for the formation of young galaxies, producing about 100 stars a year – ten times more than expected.
These may be the so-called “population III” stars that astronomers have not noticed before. These first-generation stars are “much bigger, brighter and hotter than modern + stars,” according to Fabio Bakucci of the Harvard Astrophysics Center (USA), the lead author of the study, quoted in Communications.
Another trail: the presence of a giant black hole in the heart of the galaxy. Immersing a large amount of gas will emit powerful radiation into the ultraviolet.
But for that black hole to have 100 million solar masses. Franோois Combs, an astronomer at the Paris-PSL laboratory who did not participate in the study, told AFP that “it is not very reliable to reach such a mass in such a short period of time”.
To eliminate the unknown, the HD1 galaxy was selected as the target of the James Web Space Telescope and its unparalleled ability to see the most distant universe.