An artist’s impression of the Wolfe Disk (NRAO/AUI/NSF, S. Dagnello)

Massive Rotating Disk Galaxy Existed in the Early Universe

The discovery of the Wolfe Disc — the most distant and earliest galaxy ever seen — could change our understanding of galactic formation.

Current models of massive galaxy formation suggest that they evolve as part of a slow growth process, gradually increasing in size through mergers with smaller galaxies and the accumulation of clumps of hot gas. This means that most galaxies should have reached massive size relatively late in the course of the Universe’s 13.8 billion years history.

However, the discovery of a massive rotating disk galaxy, much like our own Milky Way, when the Universe was just 1.5 billion years old calls these models into question.

ALMA radio image of the Wolfe Disk, seen when the universe was only ten per cent of its current age. (ALMA (ESO/NAOJ/NRAO), M. Neeleman; NRAO/AUI/NSF, S. Dagnello)

The discovery that the galaxy DLA0817g — nicknamed the Wolfe Disk after the late astronomer Arthur M. Wolfe — existed at such an early stage in the Universe’s development was made by a team of astronomers using the Atacama Large Millimeter/submillimeter Array (ALMA). At 12.8 billion light-years from Earth, it is currently the most distant disk galaxy ever observed. This means it is also the…