On February 28th 2018, scientists announced in the Journal Nature that a faint radio signal from deep in the universe has revealed evidence that the first stars were born 180 million years after the big bang. The discovery was made by researchers at the University of Arizona, the Massachusetts Institute of Technology (MIT) and the National Science Foundation, using a radio telescope in the Australian outback.
The first stars were formed from primordial hydrogen and helium. The researchers formulated a theory that this early star formation might have caused a slight dip in the Cosmic Microwave Background radiation. According to their theory this dip in the light left over from the big bang should be detectable. The team designed and built a kitchen table sized antennae which they called Experiment to Detect the Global EoR (Epoch of Reionization) Signatures or EDGES,
They took their antennae to the Murchison Radio-astronomy (MRO) in western Australia. The radio quiet facility allowed the team to use EDGES to scan frequencies that overlapped the FM band. EDGES was eventually able to spot the dip in the CMB at about 78 megahertz, which turned out to be twice the intensity that the researchers had expected. They further theorized that this could be due to the early hydrogen being cooled down by the presence of dark matter.
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