ALMA discovered a massive rotating galactic disk in the early Universe. The discovery made by scientists from Max Planck University is described in the journal Nature.
The galaxy that surrounds the disk is called DLA0817g or the Wolfe galaxy in honor of the astronomer Arthur M. Wolfe. The object is the most distant spinning-disk galaxy ever seen.
Wulf’s disk rotates at a speed of about 272 km / s – about as fast as the Milky Way. It was formed at an early stage in the existence of the Universe, approximately 1.3 billion years after the Big Bang.
The discovery of Wolfe’s disk poses a problem for galaxy-forming models that predict that massive galaxies at this point in the evolution of the universe have grown due to the many mergers of smaller galaxies and hot clusters of gas.
In most models, galaxies acquire a disk about 6 billion years after the Big Bang – that is, 4.7 billion years later than the Wolfe galaxy formed.
“We believe that Wolfe’s disk has grown mainly due to the continuous build-up of cold gas. However, one of the issues that remains unresolved is how to collect such a large gas mass while maintaining a relatively stable rotating disk”.
Xavier Prochaska, lead author of the research