For the first time, scientists have used Earth-based telescopes to peer back into the cosmic dawn — an era more than 13 billion years ago when light from the first stars began reshaping our universe.
The residual light from this ancient epoch is millimeters in wavelength and extremely faint, meaning that although space-based observatories have been able to peer into it, the signal is drowned out by the electromagnetic radiation in Earth's atmosphere before ground-based telescopes can detect the primordial light.
