for decades, astronomers seek to detect, without success, a very ancient sign. A is issued makes about 12,000 million years ago, shortly after the Big Bang , which holds many of the secrets that today escape us about the nature of the Universe in which we live.
Now, in an article to be published soon in Astrophysical Journal and can be found already in arXiv.org, an international team of researchers announces to have approached the goal ten times more than in any previous attempt.
The achievement has been possible using the 4096 antennas of the Murchison Widefield Array (MWA), located in the interior of Western Australia and built specifically to detect the electromagnetic radiation emitted by the neutral hydrogen , the gas that was made the Universe young when he was still only a soup burning of protons and neutrinos, born from the Big Bang.
Later, those particles root began to be grouped together to form the first stars, giving rise to a very important phase in the evolution of the Universe known as the "Epoch of Reionisation".Weakened, distorted, and polluted
According to Nichole Barry, of the University of Melbourne and lead author of the study, "defining the evolution of the Epoch of Reionization is extremely important to our understanding of Astrophysics and Cosmology. Until now, however, no one has been able to observe that. But our results are much closer to the goal."
it Is known that the neutral hydrogen that pervaded the space and the time before and at the beginning of the Epoch of Reionization emit signals at a wavelength of approximately 21 cm after its long, long journey of 12,000 million years to reach us, the initial wavelength is "stretched" to some value above two meters, due to the expansion of the Universe. That is to say, the signal continues to exist, though greatly weakened, deformed and contaminated by the huge number of galaxies that have been found in their way. To detect it, therefore, it is extremely difficult, but researchers believe that it is the best way to explore the initial conditions of the Universe.Very cool
as of 21 hours of observational data in gross, Barry and his colleagues tested a series of new techniques to refine the analysis and to exclude the numerous sources of contamination of the signal, including the potential for interference due to the radio emissions of the Earth. And the result was a level of precision almost one order of magnitude superior to those achieved up until now, which allowed to significantly reduce the range in which the Epoch of Reionization may have started.
"In fact -says for its part, Cathryn Trott, of the University of Curtin, in Australia and co-author of the study - we cannot say that this work moves us closer to date accurately the beginning or the end of the Epoch of Reionization, but discards some of the models more extreme. Now we can rule out that it happened very quickly, and also that the conditions in which it occurred were very cold."
it does Not seem much, but in reality it is a giant step forward. A genuine leap that brings us closer, every time more, many of the answers that until now the Universe has managed to hide from us.Updated Date: 17 September 2019, 21:00