This marks the “first time” this has been achieved from the surface of our planet.

The team measured the faint, polarized microwave light – a direct echo from the Big Bang.

“People thought this couldn’t be done from the ground. Astronomy is a technology-limited field, and microwave signals from the Cosmic Dawn are famously difficult to measure,” said Tobias Marriage, project leader and a Johns Hopkins professor of physics and astronomy.

Faint microwave signals

Soon after the super-explosive Big Bang, the universe was a dense, opaque fog of electrons, trapping all light. But as the universe expanded and cooled, protons and electrons combined to form neutral hydrogen atoms. Suddenly, the microwave radiation – possibly the first light — was free to travel in space.

Then came the Cosmic Dawn. The very first stars ignited, radiating immense energy that ripped electrons free from those neutral hydrogen atoms. This process, called reionization, scattered some of that ancient microwave light, leaving a unique fingerprint.