A group of researchers led by Judd Bowman, an astronomer at Arizona State University, recently made a remarkable discovery by spotting the impressions of the earliest stars in the universe.
Soon after the Big Bang, 13.7 billion years ago, the universe expanded, cooled and became very dark.
Stars and other cosmological objects hadn’t formed yet. The universe was filled with only neutral hydrogen gas.
Then, about 400,000 years after the Big Bang, and for the following 50 to 100 million years, gravity began to force the gas to collapse and gradually began to form the first stars.
Using the Commonwealth Scientific and Industrial Research Organization (CSIRO) radio astronomy facilities of the Murchison Radio-astronomy Observatory, in Western Australia, the Arizona team was able to detect radio signals produced by the ancient hydrogen gas.
The signals gave the researchers first evidence that the first stars in the universe were born a mere 180 million years after it began.