An international team of astronomers has used the Atacama telescope to obtain incredibly clear images of relic radiation that emerged 380 thousand years after the Big Bang.
The light, captured by the Atacama telescope from an observatory in the Chilean Andes, has traveled a distance of more than 13 billion years. Scientists were finally able to see, what the early Universe looked like just 380 thousand years after the Big Bang.
«We see the first steps before the oldest stars and galaxies formed. And we don’t just see light and dark, we see the polarization of light in high resolution. This is the defining factor that sets ACT apart from Planck and other previous telescopes», — say Atacama Cosmology Telescope Director Suzanne Staggs and Professor of Physics Princeton University Henry de Wolf Smyth.
As the astrophysicist from Sigurd Naess of the University of Oslo, the Atacama telescope has 5 times the resolution of the Planck telescope and significantly better sensitivity, allowing direct observation of weak polarized signals.
The images show the movement of hydrogen and helium nuclei (protons and alpha particles) in the early Universe. The researchers note that the results confirm a simple model of the Universe and refute all alternative theories.
The research paper has not yet been peer-reviewed. The authors plan to present the results at the annual conference of the American Physical Society on March 19.
During the first few hundred thousand years after the Big Bang, the Universe was filled with primary plasma, so hot that light could not spread freely. As the Universe expanded, free space between particles increased, charged particles decreased, photons stopped scattering so often and could now move freely in space, practically without interacting with matter. The relic radiation is made up of those photons that were emitted by the plasma towards the future location of the Earth at that time.
New images have provided scientists with a very clear picture of subtle variations density and velocity of gases, that filled the early Universe. The areas that look like fog clouds in the images are more or less dense areas in the hydrogen and helium cluster.
«By looking back to a time when things were much simpler, we can tell the story of how our Universe evolved to the rich and complex place we find ourselves today», — emphasizes Joe Dunkley, the Joseph Henry Professor of Physics and Astrophysical Sciences at Princeton University and leader of the ACT analysis.
According to Erminia Calabrese, professor of astrophysics at the University of Cardiff and lead author of one of the new scientific papers, the latest measurements have revealed that the length of the visible part of the Universe reaches almost 50 billion light-years in all directions. The mass of the Universe is 1900 «zeta suns» or almost 2 trillion trillion suns. Of this, the mass of baryonic matter that we are able to see and measure is only 100. The other 500 — is made up of mysterious dark matter, and the remaining 1300 — is the dominant energy of the vacuum. The total mass of neutrino particles is at most four «zeta suns».
«Almost all of the helium in the Universe was formed in the first three minutes of cosmic time. Our new measurements of its abundance are in very good agreement with theoretical models and observations in galaxies», — said Thibaut Louis, an astrophysicist at the University of Paris-Saclay and lead author of one of the scientific papers.
New measurements and calculations using the Atacama telescope have helped scientists refine estimates of the age of the Universe and the rate of its expansion at the moment. The data confirm that our Universe is 13.8 billion years old. The error in the calculations is only 0.1%.
Recently, scientists have been hotly debating the most accurate method of measuring the Hubble constant, which shows how fast the expansion of outer space is taking place. Calculations based on observations of relic radiation indicate that the expansion rate is 67-68 km/s per megaparsec. However, calculations based on the results of observations of neighboring galaxies indicate that the Hubble constant is 73-74 km/s/Mpc. The researchers used the Atacama telescope to measure the Hubble constant with higher accuracy. Their measurements and calculations are consistent with those based on observations of relic radiation.
Spelling error report
The following text will be sent to our editors: