Is called Ngp-190387, is located at a distance of over 12 billion light years from Earth and has earned headlines for the presence of an element (fluorine) which, in the form of floride, is found in our common toothpaste. It is a galaxy identified by the Alma (Atacama Large Millimeter Array) radio telescope of the Southern European Observatory (Eso) in the Chilean Andes.
The discovery
The discovery was illustrated in the article “The ramp-up of interstellar medium enrichment at z> 4”, just published in Nature Astronomy. The study, which involved an international team of researchers, was coordinated by the University of Hertfordshire Center for Astrophysics Research in the United Kingdom, and sheds new light on the processes of fluorine formation in the Universe. “It took a few tens or hundreds of millions of years for this galaxy to have levels of fluoride comparable to those found in the stars of the Milky Way, which is 13.5 billion years old. This is a completely unexpected result, “says Chiaki Kobayashi of the University of Hertfordshire.
The implications
“We all know fluoride because the toothpaste we use every day contains it in the form of fluoride – explained Maximilien Franco who led the new study – like most of the elements around us, fluorine is created inside the stars, but until now we didn’t know exactly how it was produced. We didn’t even know which type of stars produced most of the fluorine in the Universe. ” Franco and his collaborators have identified fluorine (in the form of hydrofluoric acid) in the large gas clouds of the galaxy that we see today as it was when the universe was “only” 1.4 billion years old, about 10% of its age. current. Since stars eject the elements that form in the nucleus when they reach the end of their life, this detection implies that the stars that created fluorine must have lived and died quickly.
The Wolf – Rayet stars
The team believes the most likely fluorine production sites are Wolf – Rayet type stars, very massive stars that only live a few million years. Wolf-Rayet type stars had already been suggested as possible sources of cosmic fluorine, but astronomers until now did not know how important they were in the production of this element in the early Universe.
Source-tg24.sky.it