Astronomers discover oldest disk galaxy hidden deep in the cosmos

New discovery of large disk galaxy hidden in shadows at the edge of the universe.

The Wolfe Disk is a massive rotating disk from the earliest days of the universe.

In a new study, published in the journal Nature on Wednesday, an international team of astronomers detected light from an ancient, huge disk-shaped galaxy in a far corner of the universe. The light took 12.5 billion years to reach Earth, meaning that the disk formed around 1.5 billion years after the Big Bang during the earliest days of the universe.

Using the Atacama Large Millimeter Array or ALMA, one of the world’s most powerful telescopes, a research team found the galaxy when it was studying light coming from a distant, huge black hole known as a quasar. Some of the light from the new galaxy was absorbed before heading toward earth, revealing the shape of the universe in dark space. Through ALMA and other data from the Hubble Telescope, the team was able to more clearly resolve some of its features.

“Previous studies hinted at the existence of these early rotating gas-rich disk galaxies,” said Marcel Neeleman, an astronomer at the Max Planck Institute for Astronomy and lead author on the study. “Thanks to ALMA we now have unambiguous evidence they occur as early as 1.5 billion years after the Big Bang.”

The newly discovered galaxy has been officially named DLA0817g, but the team nicknamed it the Wolfe Disk in honor of astronomer Arthur M. Wolfe.

Comparing observations with analytical models, the team determined that that the dark object was is a galaxy made of a dusty, gaseous disk spinning at approximately 169 miles (272 kilometers) per second, with an estimated mass 50 to 100 times more than the sun.

The research team also believes the Wolfe Disk galaxy is forming stars at an incredibly fast rate. According to Xavier Prochaska, astronomer at the University of California, Santa Cruz and a co-author on the study, DLA0817g “must be one of the most productive disk galaxies in the early universe.”

The discovery provides some clues about how galaxies are built and why we so often see the structures resembling huge disks, while in other cases they are not visible.