Dark matter nursery and its monstrous baby galaxies found

Washington: A nest of monstrous baby galaxies, 11.5 billion light-years away could help answer questions about how the known universe formed.

Using the Atacama Large Millimeter/submillimeter Array (ALMA), astronomers discovered the young galaxies that seem to reside at the junction of gigantic filaments in a web of dark matter. These findings are important for understanding how monstrous galaxies like these are formed and how they evolve in to huge elliptical galaxies.

We are living in a relatively quiet period in the history of the Universe. Ten billion years ago, long before the Sun and Earth were formed, areas of the Universe were inhabited by monstrous galaxies with star formation rates hundreds or thousands of times what we observe today in the Milky Way galaxy.

There aren't any monstrous galaxies left in the modern Universe, but astronomers believe that these young galaxies matured into giant elliptical galaxies which are seen in the modern Universe.

With ten times better sensitivity and 60 times better resolution, ALMA enabled astronomers to pinpoint the locations of nine monstrous galaxies in SSA22. The team found that their young monstrous galaxies seemed to bewere located right at the intersection of the dark matter filaments. This finding supports the model that monstrous galaxies form in areas where dark matter is concentrated. And since modern large elliptical galaxies are simply monstrous galaxies which have mellowed with age, they too must have originated at nexuses in the large scale structure.

This result is a very important step for a comprehensive understanding of the relation between the dark matter distribution and monstrous galaxies. The team will continue its extensive search for monstrous galaxies to look back even farther into the early history of the Universe to study the evolution of the large scale structure.

The study appears in Astrophysical Journal Letters.