Astronomers close in on ancient signal from 'one of the most unexplored periods in our universe'

An image of part of the sky seen in radio wavelengths. New research removed many sources of nearby radio “noise” to focus on some of the earliest light in the universe.

Long before starlight filled the cosmos for the first time, the young universe may have been simmering, according to a new study.

The findings suggest that about 800 million years after the Big Bang, energy from newborn black holes and the fading embers of the first stars was already warming vast clouds of intergalactic hydrogen gas, offering a rare glimpse into a largely uncharted chapter of the universe's youth.