Abigail BanerjiMar 19, 2021 09:58:36 IST
Looking into the early Earth around 12 billion years ago, scientists in France are for the first time on the spherical filaments of hydrogen gas known as the “cosmic net,” they said Thursday. Cosmological models have been making predictions for a long time, but so far the cosmic web has not been directly observed and captured in images. Eight months of observation with the Southern Observatory ‘s Very Large Telescope and a year of data crushing showed the filaments with only one to two billion years after the Big Bang.
The image shows the light emitted by hydrogen atoms in the cosmic net in an area of about 15 million light-years across. In addition to the very weak emission from interstellar gas, several point sources can be seen: these are galaxies that form their first stars. Image credit: CNRS / Jeremy Blaizot / SPHINX projet
But the biggest surprise, scientists said, is symbols showing that light came from billions of previously invisible – and unexpected – dwarf galaxies spawning trillions of stars.
The findings were reported in the journal Astronomy & Astrophysics.
“After a period of initial darkness, the Universe exploded with light and emitted a large number of stars,” lead author Roland Bacon, a scientist at the Center for Astrophysics Research in Lyon, told AFP.
“One of the big questions is what ended that time of darkness,” continues to a degree in the first Universe called re-ionization, he said.
Until now, astronomers had only captured partial and indirect views of the cosmic net through quasars, which have powerful radiation, like car lights, reflecting gas clouds on the line of sight.
But these regions do not represent the entire network of filaments where most galaxies were born – ourselves included.
Plumbing new depth
“These conclusions are fundamental,” said Emanuele Daddi, a researcher at the Atomic Energy Commission who did not take part in the study. “We have never seen the release of gases on this scale, which is essential for understanding how galaxies perform.”
The team trained a very large ESO Telescope – equipped with a 3D spectrograph called MUSE – at one area of the sky for over 140 hours. Together, the two instruments are one of the most powerful observation systems in the world.
The selected region is part of the Hubble Ultra-Deep Field, which contains the deepest image of the cosmos ever found.
But the new images drop new depths of the original Universe – 40 percent of recently discovered galleries were beyond the reach of Hubble.
While these galaxies – 10 to 12 billion light years away – are too weak to be discovered on their own with conventional instruments, they are likely to strengthen and challenge existing models. already of galaxy formation.
Scientists are no longer beginning to study their effects, the researchers said.
Astronomers at the Lagrange laboratory for the University of Cote d’Azur have contributed to the research.