Scientists working from rural Western Australia have tuned into radio waves that pre-date the birth of galaxies, ruling out the possibility of a cataclysmic event of numerous stars being simultaneously produced.
All it took for two US researchers was a simple set-up of a computer, antenna, amplifier and some circuits hooked up to solar-power to pinpoint the extremely faint signals from billions of years ago.
Arizona State University's assistant professor Judd Bowman and Massachusetts Institute of Technology's Alan Rogers last year installed their radio at the Murchison Radio-astronomy Observatory, about 750 kilometres north of Perth, searching for the hydrogen gas that existed before stars or galaxies were formed.
In a research letter published in today's Nature journal, Bowman and Rogers said their groundwork ruled out the possibility of a disruptive event resulting in the simultaneous formation of stars.
"This (hydrogen) gas would have emitted a radio line at a wavelength of 21 centimetres – stretched to about two metres by the time we see it today, which is about the size of a person," assistant professor Bowman said.
He said the formation of those galaxies forced the radio line to disappear, telling scientists when and how the first galaxies evolved.
"These findings are significant because we have shown that it is possible to study the early universe using an entirely new technique of probing radio emission from the gas between galaxies," he said.
"This technique is expected to be very powerful and should provide new ways to indirectly study how structures like stars, galaxies, and black holes formed in the universe and influenced their environments."
University of Western Australia physics professor Peter Quinn said that after the Big Bang - which is thought to have created the universe - the intense heat began to dissipate as the universe expanded creating the "cooling" hydrogen gas.
"Now along comes the very first star to be formed at certain places where it happens to be a bit more dense, and some of the first stars began to form and give out energy and heat," professor Quinn said.
"(This) marks that time in the history of the universe that the very first objects were formed."
That process took between three and 12 million years, assistant professor Bowman said, much faster than current theories predict.
"But it is very much an open question right now to understand the relationship between the first galaxies and their environments," he said.
"The most important aspect of these measurements is that we have demonstrated an entirely new tool to help us understand the formation and evolution of the first stars and galaxies in the early universe."
Professor Quinn said regional WA was the world's best place to complete radio-astronomy studies because researchers did not have to contend with FM radio signals.
"You want to go to an isolated place where the radio signal is very quiet, where interference is very low and look at this extremely weak signals.
Assistant professor Bowman said he and Mr Rogers would return to WA in January to continue their observations.
