One of the Holy Grails in cosmology is a look back at the earliest epochs of cosmic history. Unfortunately, the universe’s first few hundred thousand years are shrouded in an impenetrable fog. So far, nobody’s been able to see past it to the Big Bang. As it turns out, astronomers are chipping away at that cosmic fog by using data from the Atacama Cosmology Telescope (ACT) in Chile.

ACT measured light first emitted in the baby universe some 380,000 years after the Big Bang. According to the Consortium director Suzanne Staggs, that measurement opened the window to a time when the first cosmic structures were starting to assemble. “We are seeing the first steps towards making the earliest stars and galaxies,” she said. “And we’re not just seeing light and dark, we’re seeing the polarization of light in high resolution. That is a defining factor distinguishing ACT from Planck and other, earlier telescopes.”

The clearer data and images from ACT are also helping scientists understand just when and where the first galaxies began to form. If the ACT data are confirmed, they represent the earliest baby picture of the universe, showing scientists what the seeds of galaxies looked like only a few hundred thousand years after the Big Bang.

The clearest and most precise images yet of the universe in its infancy—the earliest cosmic time accessible to humans—have been produced by an international team of astronomers.

Measuring light, known as the cosmic microwave background (CMB), that traveled for more than 13 billion years to reach a telescope high in the Chilean Andes, the new images reveal the universe when it was about 380,000 years old—the equivalent of hours-old baby pictures of a now middle-aged cosmos.

The research, by the Atacama Cosmology Telescope (ACT) collaboration, shows both the intensity and polarization of the earliest light after the Big Bang with unprecedented clarity, revealing the formation of ancient, consolidating clouds of hydrogen and helium that later developed into the first stars and galaxies.

Astronomers have identified a bright hydrogen emission from a galaxy in the very early universe. The surprise finding is challenging researchers to explain how this light could have pierced the thick fog of neutral hydrogen that filled space at that time.

A key goal of the NASA/ESA/CSA James Webb Space Telescope has been to see further than ever before into the distant past of our universe, when the first galaxies were forming after the Big Bang, a period known as cosmic dawn.

Researchers studying one of those very early galaxies have now made a discovery in the spectrum of its light, that challenges our established understanding of the universe’s early history. Their results are reported in the journal Nature.

Our universe may not be the only universe, either