In our 13.8 billion-year-old universe, most disk galaxies like our Milky Way were thought to form gradually, reaching their large mass relatively late. But now astronomers led by Marcel Neeleman from the Max Planck Institute for Astronomy, using the ALMA observatory, have found a massive rotating disk galaxy, seen when the universe was only ten percent of its current age. The observation shows that some disk galaxies must have formed much more quickly. This supports earlier computer simulations that had indicated the role of a quick, "cold" mode of galaxy formation. The results have been published in the journal Nature.