In a landmark discovery, researchers in Europe have spotted star-forming gas clouds billions of light years away, which are probably the building blocks of some of the first galaxies in the universe. According to a report from UPI, astronomers noticed the clouds by peering deep into space, past brighter light sources and into the earliest reaches of time.

Researchers at the European Southern Observatory in Chile used the ALMA telescope to gaze back towards the very start of the universe. They pointed the telescope at some of the oldest charted galaxies, some of which appeared only 800 million years after the Big Bang.

They noticed the sign of glowing carbon to the side of one of these ancient galaxies, called BDF 3299. According to astronomer and the study’s co-author Andrea Ferrara from Italy’s Scuola Normale Superiore, “This is the most distant detection ever of this kind of emission from a ‘normal’ galaxy, seen less than one billion years after the Big Bang. It gives us the opportunity to watch the build-up of the first galaxies.”

After the giant explosion precipitated by the Big Bang, space was abound with gas clouds formed of dust. As these clouds started to coalesce into stars through a process called reionization, the clouds dissipated and became hard to see.

Scientists say that the iridescent gas discovered by ALMA comes from BDF 3299 because it has left from the middle of the galaxy, pushed away by the energy created by young stars.

The new findings could offer insights into how our universe was created, and will likely open up a brand new line of research that could change our understanding of star formation and the origins of distant galaxies.